What is the carnivore diet? (Introduction)

The carnivore diet is a diet in which adherents consume only animal products.

carnivore food…

Examples of foods consumed on the carnivore diet include:

Beef

Chicken

Dairy products (butter, cheese, milk)

Eggs

Fish & shellfish

Lamb

Organ meats (liver, heart, brain, etc.)

Roe

Many carnivore diet practitioners like Paul Saladino (MD) recommend a nose-to-tail style of eating to minimize risk of nutrient deficiencies.

However, other carnivore diet practitioners like Shawn Baker (MD) state that a nose-to-tail style of eating (with organ meats) is unnecessary.

On the carnivore diet, most experts suggest that it’s acceptable to season meat with a little salt and pepper, however, no additional seasoning is recommended.

Some carnivore diet experts also recommend being mindful of the temperatures at which meats are cooked – as cooking meat at high temperatures leads to the formation of heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PCAHs).

High intakes of HCAs and PCAHs can cause various types of cancer in susceptible persons.

And while many carnivore diet practitioners recommend excluding dairy products, others claim that inclusion of select dairy products may be nutritionally beneficial – particularly among individuals devoid of dairy sensitivities or intolerances.

Some individuals have created their own variations or spin-offs of the carnivore diet including:

Cyclical carnivore diet wherein an individual may cycle between: zero-carb carnivore and keto OR zero-carb carnivore and an omnivorous style of eating.

Modified carnivore diet that includes select non-animal foods (e.g. vegetables or fruits for fiber in small amounts for a hormetic effect).

Origins of the carnivore diet

The carnivore diet was likely followed by select indigenous tribes and explorers throughout human history out of necessity – not necessarily out of choice.

Although some people were consuming carnivore diet long before it became an internet trend, the carnivore diet wasn’t on most people’s radar until ~2018.

During 2018, the carnivore diet exploded into mainstream consciousness after being heavily promoted online by orthopedic surgeon Shawn Baker (MD).

Shawn Baker rapidly accrued a large [cult-like] following on YouTube and thereafter was invited on the Joe Rogan Experience to discuss the carnivore diet – which got more people interested in its potential health effects (both good and bad).

Shortly thereafter, the likes of Jordan Peterson and Mikhaila Peterson – each of whom claimed to have derived substantial subjective benefit from the carnivore diet – shared favorable anecdotes associated with the diet on the Joe Rogan Experience.

Though the carnivore diet is extreme, its proponents claim that following a carnivore diet has significantly improved their overall health and/or subjective wellbeing.

Carnivore and/or Zero Carbohydrate Diets (Case Reports)

Included below are (1) case reports of carnivore, zero-carbohydrate diets AND (2) papers discussing meat-only or all-meat diets in humans.

In February 1886, a letter printed in The British Medical Journal briefly documented one man’s experiment with a carnivore diet.

The man named Ben Rhydding from Leeds, United Kindgom reportedly read a recommendation from a Dr. Salisbury who used the diet to treat obesity.

Ben Rhydding reported that 7 years prior to February 1886, he weighed around 166 lbs. at 5 feet 9 inches tall.

During his physical training throughout college, he lost 5 lbs. and dropped to 161 lbs.

However, after college he gained a significant amount of weight and ended up at 196 lbs.

In effort to lose weight, he lived on only “lean meat and hot water” for 6 weeks.

A normal day of eating and drinking for Ben included:

7:00 AM: Hot water (1 pint at 130 F)

8:30 AM: Beefsteak (1 lb.)

11:30 AM: Schoolroom tea (1 pint w/ squeeze of lemon)

1:30 PM: Beefsteak (1.25 lbs.)

3:30 or 4 PM: Schoolroom tea (1 pint w/ squeeze of lemon)

6:30 PM: Beefsteak (1 lb.)

10 PM: Hot water (1 pint at 130 F)

It was noted that Ben varied his meat intake with chicken, hare, and other lean meats.

What were the results of Ben’s 6-week carnivore diet experiment?

Lost 14 lbs. total. He lost a total of 14 lbs. while following this diet for 6 weeks.

Lost 6 inches in girth. He lost 6 inches from his waist… allowing him to fit into smaller clothes. After the weight loss, he transitioned to gloves and shoes a size smaller – and his tailor was “in despair” (funny).

Muscle building. He said that his muscles were hardening

Digestion improved. He reported that his “flatulent indigestion” completely vanished.

Mental energy & clarity. He reported that his mental activity and clarity seemed to have “doubled” – claiming that he spoke for an hour with less effort than when he spoke for 10 minutes in December.

Sleep enhancement. He reportedly slept for 7 hours without moving while on this diet.

Gouty deposits disappeared. He reported that gouty “heirlooms” in the shape of “hereditary” deposits disappeared throughout his body.

Compliments about appearance. He reported receiving numerous compliments from friends about his “aldermanic” appearance.

Normal kidney function. He reported that his kidneys were functioning well throughout the experiment.

The takeaway from this case report is that the carnivore diet was an effective short-term tool for weight loss and body recomposition (fat loss with muscle gain) over a 6-week period.

In the aforementioned case, the carnivore diet was associated with improvements in other aspects of health including: cognition; energy; sleep; digestion; and gout.

William A. Thomas, a medical doctor (MD) from Chicago, published a paper discussing the health of an exclusively carnivorous Eskimo race.

The purpose of this paper was to present findings from a survey by Thomas which sought to evaluate: (1) food sources, composition, and preparation; (2) renal function; (3) rates of vascular disease; (4) rates of scurvy and rickets – among Eskimos on a high-protein, meat-based diets.

Thomas administered the survey to the Eskimos during the MacMillan artic expedition of 1926 wherein he was in close contact with Eskimos of Greenland and Eskimos of Northern Labrador.

It was noted that most Eskimos were isolated from Europeans – but that some were examined under hospital conditions with laboratory facilities at hand – and some Eskimos were employed as house servants and laborers for Danes.

Although some Eskimos had access to a very small amount of European food – most did not.

All of the Eskimos lived on an exclusively carnivore diet since weaning in part due to the fact that there was no edible vegetation.

The diet for these Eskimos consisted of various animal products, including:

Whale

Walrus

Seal

Caribou

Musk ox

Hare

Polar bear

Fox

Ptarmigan

Sea birds (geese, duck, auks, gulls)

Fish

It was noted by Thomas that most of the Eskimos preferred to eat these foods raw.

Additionally, contrary to popular belief, Thomas stated that the Eskimo consumes very little animal fat or blubber.

Instead, the fattiest parts of meat were used for oils: (1) in lighting and warming homes; (2) to aid in melting ice and snow for drinking; and (3) to occasionally cook food.

Furthermore, it was reported that Eskimos preferred consuming red meat – the flesh and the liver.

Among the 142 adult Eskimos examined, albumin was found in the urine of 12 – none of which exhibited evidence of circulatory disease.

Of the 12 adults with urinary albumin: 3 had systolic blood pressures above 140 – and 9 had traces of albumin with no increased blood pressure.

For reference: Albumin is a protein found in the blood. A healthy kidney doesn’t let albumin pass from blood into the urine – whereas a damaged kidney does. High albumin in the urine is a sign of kidney disease.

In total, there were 9 adults with hypertension and 12 adults with albuminuria (3 of these adults had both conditions).

Nephritic edema was observed in 1 adult Eskimo without comorbidities such as cardiac disease, varicose veins, and phlebitis.

Urinary casts (microscopic cylindrical structures produced by the kidney in diseased states) were discovered via microscopy assays in 11 adults.

A total of 9 adult Eskimos over the age of 60 years old were examined, with only 1 exhibiting albumin in the urine – and 2 exhibiting casts.

The Eskimo men exhibited extraordinary strength and endurance, often traveling 24 to 36 hours nonstop without food or rest.

This led Thomas to conclude that, under the living conditions and lifestyle of the Eskimos, an exclusively carnivorous diet does NOT cause renal or vascular disease.

What about vitamin deficiencies? According to Thomas, none of the exclusively carnivorous Eskimos exhibited scurvy or rickets.

It was noted that the Eskimo children were nursed for 4 to 6 years until their teeth became strong enough to eat meat.

Contrast the aforementioned healthy Eskimos of Greenland to the Eskimos of Labrador – and there are notable differences.

Thomas discovered that, for years, the Eskimos of Labrador were in close contact with influence from non-native civilization – causing many to abandon native dietary habits.

Furthermore, because wood is plentiful for the Eskimos of Labrador, they usually consume cooked meat (rather than raw).

In addition to consuming cooked meat, Eskimos of Labrador trade their furs to outsiders for various foods such as: dried potatoes, flour, canned goods, cereals, and cereal products – but no vegetables.

In the Eskimos of Labrador, rates of scurvy and rickets are high – as well as other maladies such as: rheumatic pain, joint stiffness, and fatigue.

An editorial published on September 20, 1930 in the Journal of the American Medical Association (author unreported) discussed whether meat consumption is healthy.

The author stated that meat in the modern diet is a contentious subject for many – and is influenced by religious, economic, geographic, and sociologic factors.

Some people avoid meat due to religious or sociological teachings – whereas others may not have access to meat (due to geographic location and/or finances).

It was stated that students of nutritional science should not be influenced by anti-meat teachings.

Instead, these students should attempt to objectively examine the effects of dietary meat consumption on human health.

The author noted that flesh foods were initially incriminated due to the fact that they contained purines, precursors to uric acid (a catabolite which many suspected caused human health problems).

However, with continued investigation and experimentation, many people shifted their views on animal foods from: perceiving them as unhealthy to perceiving them as healthy.

By 1930, the author reported that most people were no longer concerned about avoiding or minimizing intake of purines because science showed that purines don’t typically cause health problems.

As an example, the author highlighted a drastic change in the mainstream perception of liver consumption.

The initial mainstream view of liver was: it’s unhealthy due to its purine content – but this changed over time such that [eventually] the mainstream perception of liver became: it’s healthy due to its nutrient density.

Specifically, in the early 1900s, many suspected that meat consumption could cause kidney disorders and arterial hypertension.

This editorial initially references research by Thomas (1927) in which blood pressure and renal function appeared normal in a majority of 142 adult Greenland Eskimos on a meat-based diet.

The editorial then discussed a series of publications by McClellan et al. (1930) in which the health effects of a meat-only diet were formally tracked in a series of meticulous observations in 2 arctic explorers.

The arctic explorers observed by researchers lived for a full year on a diet consisting solely of “flesh foods.” Such flesh foods included:

Beef

Lamb

Veal

Pork

Chicken

It was noted that the arctic explorers used the: muscle, liver, kidneys, brain, bone marrow, bacon and fat – of these animals.

In this observational study, the average macronutrient intakes of the explorers were as follows:

Protein: 100 to 140 grams/day

Fat: 200 to 300 grams/day

Carbs: 7 to 12 grams/day (derived from meat)

Total daily energy intake: 2000 to 3000 calories

What were the effects of the carnivore diet in these explorers after 1 year?

Mentally alert

Physically active

Normal blood pressure

Normal kidney function

No vitamin deficiencies

Mild ketosis

The report stated that the explorers: were mentally alert, physically active, and showed no specific changes in any system of the body.

It also stated that there was no evidence of renal damage or vitamin deficiencies in these men.

Furthermore, the routine consumption of meats did not affect GI tract absorption.

The only adverse finding in the men was that, while consuming meat and fat alone, they exhibited negative calcium balance.

Carnivore diet benefits

Followers and promoters of the carnivore diet claim that it helps with an assortment of health problems. Additionally, the carnivore diet may have potential to enhance health in select individuals who are already (relatively) healthy.

carnivore supply

Included below is a list of potential benefits associated with the carnivore diet. Understand that because the carnivore diet hasn’t been extensively researched – it’s unclear as to whether all of these hypothesized benefits are legitimate.

Anti-inflammatory

The carnivore diet might help decrease systemic inflammation for some individuals.

The anti-inflammatory effect derived from a carnivore diet is probably attributable to one or more of the following mechanisms:

Unless you follow a nose-to-tail style of eating (including organ meats, egg yolks, etc.) – odds are you’ll end up with at least mild nutrient deficiencies (particularly with vitamin C).

Among persons with overactive immune systems (such as is the case with autoimmune disorders), these mild immune deficits may suppress immune function (to varying degrees) – leading sufferers to report symptom improvements.

Reversal of nutrient deficiencies (?)

Although I agree with the scientist’s proposed mechanism in the case of autoimmunity, I also think it’s possible that the carnivore diet reverses some nutrient deficiencies – particularly among persons who were previously consuming nutritionally-inadequate diets – which might beneficially modulate autoimmunity.

Because the carnivore diet makes it easy for most people to lose weight (especially body fat/adiposity), this is likely a key mechanism by which autoimmune symptoms decrease among those following the carnivore diet.

Lower systemic inflammation

High levels of inflammation are associated with a worsening of autoimmune disorder symptoms.

Decreasing inflammation such as by taking anti-inflammatory medications is generally associated with improvement in autoimmune disorder symptoms.

Because the carnivore diet has potential to decrease inflammation via multiple mechanisms (weight/fat loss and eliminating foods/compounds to which a person has an allergy/sensitivity) – this could lead to improvements in autoimmune disorders.

As of current, no research has been done to determine whether the carnivore diet is capable of reversing intestinal permeability (leaky gut) while simultaneously increasing probiotic bacteria and overall microbial diversity.

Because an overactive immune system may be triggered (in part) by intestinal permeability, allowing food particles, toxins, and bacteria to leak outside of the small intestine – whereby an immune response occurs.

Fiber and other compounds may worsen preexisting intestinal permeability (leaky gut) for some individuals.

A carnivore diet may allow the gut to heal (due to elimination of fiber) wherein no more particles, toxins, or bacteria leak from the small intestine – and the corresponding immune response (and inflammation) associated with the intestinal permeability is corrected.

As a result, symptoms of autoimmune disorders (and the gut microbiome) may drastically improve once the epithelial barrier is restored on a carnivore diet.

Blood sugar stability

Blood sugar stability may significantly improve for some individuals during a carnivore diet.

Since the carnivore diet is high in protein, the body oxidizes protein for fuel and converts the rest into glucose for energy via gluconeogenesis.

Although epidemiological studies show that higher meat intake is associated with high blood sugar (hyperglycemia) and insulin (hyperinsulinemia) – these studies do not prove causality.

Reductions in body fat, gains in lean mass, and weight loss – are all associated with improvements in blood sugar regulation.

Therefore, it’s not farfetched to suspect that individuals notice or report normalization of blood sugars while consuming carnivore.

Body recomposition (fat loss, muscle gain)

Because the carnivore diet tends to be high in bioavailable protein, most carnivore dieters will experience favorable changes in body composition without much effort.

Specifically, most carnivore dieters (particularly those who are overweight or “skinny fat”) will report simultaneous fat loss and lean mass (muscle) gain or, at the very least, lean mass preservation.

Most individuals did not consume as much protein (grams per day) pre-carnivore in comparison to while on the carnivore diet – as most animal products are high or ultra-high protein.

After transitioning to the carnivore diet, it often becomes difficult to eat as many calories as pre-carnivore due to the satiating effect of protein (protein is the most satiating macronutrient).

Furthermore, some carnivore dieters tend to eat similar, repetitive foods each day (e.g. beef) – and consuming similar foods is associated with reduced calorie intake.

Protein also has a higher thermic effect of food (TEF) relative to carbs and fats – meaning the body expends slightly more energy metabolizing protein than other macronutrients.

Additionally, the body generally has a difficult time storing protein as body fat – so if most calories in one’s diet are coming from protein, fat loss is a likely outcome.

Reducing calories in the context of a high-protein diet even if unintentional (e.g. due to the high satiation effect of protein) and increasing thermogenesis (via increasing protein intake) tends to yield fat loss.

Moreover, because protein intake remains high or ultra-high on the carnivore diet, individuals with low lean mass may experience gains in lean mass – along with fat loss.

Persons with substantial preexisting lean mass (e.g. bodybuilders) prior to a carnivore diet should, at the very least, will likely experience preservation of lean mass due to the high protein intake on carnivore.

Hormonal irregularities, high blood glucose, and (potentially) local demyelination of nerves can induce peripheral neuropathies like carpal tunnel syndrome.

Since high-protein/moderate-fat/low-carbohydrate diets have been shown to balance hormones, stabilize blood glucose, and potentially promote myelinogenesis (regeneration of myelin), there’s reason to suspect that this combination of effects would occur on a carnivore diet.

Cognitive enhancement

There are legitimate reasons to suspect that some individuals may experience cognitive enhancement on the carnivore diet (relative to a previous way of eating).

IGF-1 levels: IGF-1 is important for many cognitive functions. The carnivore diet provides plenty of IGF-1 (insulin-like growth factor-1) which helps fuel the brain.

Low levels of IGF-1 are associated with cognitive impairment and decline – whereas adequate levels are associated with optimal or enhanced cognitive performance.

Among individuals with suboptimal IGF-1 levels (prior to the carnivore diet), it’s very likely that a substantial IGF-1 boost from animal products on the carnivore diet will yield cognitive enhancement.

These amino acids are critical for the synthesis of neurotransmitters such as: acetylcholine, dopamine, GABA, glutamate, norepinephrine, and serotonin – each of which can impact cognition.

The specific type of protein consumed (animal vs. plant), quantity of protein consumed, and ratio of protein to carbohydrate consumed during meals – may influence synthesis rates and concentrations of neurotransmitters within the human brain.

Nutritional status: Assuming carnivore dieters are following a nose-to-tail style of eating in which organ meats are consumed (e.g. brain, heart, liver, etc.) – there may be a significant improvement in one’s nutritional status during the carnivore diet (compared to pre-carnivore).

It is known that micronutrient bioavailability of animal products is significantly greater than that of plants.

In other words, the nutrients from grass-fed beef and beef liver will be more efficiently absorbed within the human body than nutrients derived from plants.

Grass-fed beef contains high concentrations of vitamin B12, vitamin B6, iron, zinc and omega-3 fatty acids – all of which are efficiently absorbed.

Beef liver contains high concentrations of vitamin A (retinol), vitamin B12, vitamin C, iron, and vitamin B6 – all of which are efficiently absorbed.

Persons consuming suboptimal vegan, vegetarian, and omnivorous diets may believe their nutrient intakes are sufficient, however, if most nutrients from one’s diet are attained from plants – it’s unclear as to whether they’ll be efficiently absorbed within the body.

It is suspected that many people throughout the world have subclinical nutrient deficiencies – possibly due to lack of animal products (in some cases) and/or gene mutations that disallow efficient absorption of certain plant-based vitamins (e.g. vitamin A). (R)

Glucose stability: Unless doing a carnivore-keto diet, the body will still be using glucose as its primary fuel source via conversion of animal protein to glucose via gluconeogenesis.

Glucose is not only used more efficiently than ketones, but it’s the preferred fuel source for the brain.

As has already been mentioned earlier in this article, the carnivore diet helps to stabilize blood glucose concentrations – as high-protein, low-carb (in this case zero carb) diets are associated with improvements in blood sugar regulation.

Blood glucose stability may be further enhanced by one’s weight loss, fat loss, and lean mass gains on the carnivore diet.

On the standard American diet (SAD), many people will experience a combination of post-meal blood sugar spikes – followed by crashes (post-prandial dips).

High systemic inflammation is associated with neurotransmitter irregularities, oxidative stress, and cognitive dysfunction.

Assuming one has high systemic inflammation pre-carnivore, and the carnivore diet significantly decreases this inflammation – it’s reasonable to suspect notable improvements in cognitive function during the carnivore diet.

What are the effects of cognitive enhancement from a prior state of cognitive impairment? Possibilities include: increased productivity and motivation plus mood enhancement.

Energy level

Another benefit reported by individuals following the carnivore diet is increased energy (physical and mental).

Although transient dips in energy while transitioning to the carnivore diet are common – many people report substantial increases in energy once fully adapted to the carnivore diet.

Blood sugar stability: Perhaps the top reason for an improvement in energy level while on the carnivore diet (relative to pre-carnivore) is its ability to stabilize blood sugar.

Constant fluctuations (spikes and dips) in blood glucose are associated with fatigue and unpredictable changes in one’s energy level (e.g. hyperactivity followed by a crash).

Because a carnivore diet contains high protein and zero carbohydrates to stabilize blood sugar, carnivore dieters may be less prone to energy spikes/dips – and instead might experience stable energy levels (physical and mental) throughout the day.

Health improvement: Many people claim to experience significant health benefits on a carnivore diet – such as the reduction in symptoms of autoimmune conditions.

Nutritional status: Select carnivore dieters may experience notable improvements in nutritional status (e.g. levels of important vitamins like B12) relative to pre-carnivore – due to the fact that the bioavailabilities of nutrients in animal products are extremely high.

Improvement in nutritional status could easily ameliorate fatigue and lead some individuals to report increased energy and vigor.

Placebo effect: Nobody wants to be told that the increase in energy that they’re experiencing from the carnivore diet is attributable to a placebo effect, however, the possibility shouldn’t be dismissed.

Body recomposition: Body composition can have a strong effect on energy level. Someone without much muscle and a lot of fat (even if relatively “skinny”) is more likely to be low energy compared to someone with more muscle and less fat.

A paper by Vanhauwaert et al. (2015) (R) noted that a low-residue, low-fiber diet may have therapeutic value in the management of gastrointestinal diseases and clinical situations, including:

Bowel obstruction

Chron’s disease

Constipation

Diverticulitis

Diverticulosis

Infectious gastrointestinal disease

IBS (Irritable bowel syndrome)

Neoplastic disease

Post-abdominal surgery

Ulcerative colitis

IBS (Irritable Bowel Syndrome)

Vanhauwaert et al. state that a byproduct of fiber fermentation is gas – which can cause unpleasant side effects like abdominal pain, cramping, and distention.

In the case of IBS, Vanhauwaert et al. note that while a high-fiber diet is often promoted as a treatment, some studies show exacerbation of IBS symptoms with fiber increases.

Furthermore, a trial by Woolner and Kirby indicates that a low-fiber diet (10 g/d for 4 weeks) might actually be an effective treatment for IBS. Symptoms such as diarrhea, bloating, stomach pain, and flatulence dramatically improved. (R)

Diverticulosis

Many experts in gastric disorders suggest that diverticulosis may be caused by inadequate dietary fiber intake.

However, findings from a cross-sectional study by Peery et al. (2012) suggested that a high-fiber diet and increased bowel frequency were associated with greater risk of diverticulosis. (R)

Another study by Peery et al. (2013) involving 539 patients with asymptomatic diverticulosis suggested that a low-fiber diet was NOT associated with an increased risk of diverticulosis. (R)

Other researchers like Wick report that patients with diverticular disease actually experience fewer symptoms with consumption of low-fiber diets during symptomatic periods. (R)

Constipation

High-fiber diets are generally recommended for the treatment of constipation, however, addition of fiber to one’s diet may not always be effective.

A case-control study by Ho et al. (2012) found that a no-fiber diet substantially reduced symptoms of idiopathic constipation in 63 individuals. (R)

Gut microbiome

The gut microbiome has received a lot of hype – with many testing services and “gurus” popping up online claiming to analyze it and tell you whether your gut is healthy.

Gut bacteria abnormalities have been “linked” to many medical conditions, however, a link should not be misinterpreted as a cause.

In reality, gut microbiome composition is probably more of a response/reaction to (and possibly a reinforcer for) one’s medical status, diet, environment, and lifestyle (sleep, stress, exercise) – than the reason for good or bad health.

Although some studies show that high-fiber intake and low saturated fat intake are associated with favorable improvements in gut microbiome composition – this does NOT mean that the gut microbiome somehow worsens on the carnivore diet.

In fact, some carnivore dieters have tested their gut microbiomes pre-carnivore and post-carnivore only to report significant improvement in healthy bacteria and microbial diversity with the carnivore diet.

Beef and casein protein: Had higher levels of amino acids than the chicken protein group.

Soy protein intake was associated with higher levels of short-chain fatty acids, but the relative abundance of beneficial bacteria was reduced – and the detoxification/defense responses in the host liver were higher than in meat protein groups.

However, soy protein over a long-term resulted in upregulation of transcription factor CD14 and LPB (lipopolysaccharide-binding protein) in the liver, indicative of elevated bacterial endotoxins.

Long-term intake of meat proteins led to of a more balanced gut bacteria composition – and decreased antigen load plus inflammatory responses from gut bacteria to host.

A study by Madsen et al. (2017) suggests that casein and other dairy proteins may be the most efficient protein sources in preventing obesity, providing BCAAs, and favorably improving the gut microbiota. (R)

Since some individuals consume dairy on a carnivore diet, it could be that dairy proteins are enhancing microbial diversity within the gut.

At this juncture, most research on dietary protein and the gut has been conducted in animal models – and cannot be generalized to humans.

Nevertheless, preliminary evidence supports the idea that the foods consumed on a carnivore diet (e.g. chicken, beef, and dairy) – seem to improve composition of the gut microbiome.

Although it’s fun to think about the ways in which a carnivore diet impacts gut bacteria, realize that gut bacteria populations are NOT a reliable measurement of one’s health.

Moreover, among carnivore dieters who consume the same foods daily, it’s possible that lack of dietary diversity (i.e. eating the same foods) may improve gut health for some people because gut bacteria won’t need to constantly shift/adjust to accommodate for different foods and macronutrients.

Hormone levels

In some cases, a carnivore diet may favorably modulate production and concentrations of hormones throughout the body.

Hormones that may be modulated by the carnivore diet include (but are not limited to):

A study by Hu et al. (2015) (R) involving 148 adults assigned to either a (1) low-carb or (2) low-fat diet reported that the low-carbohydrate diet increased peptide YY concentrations to a greater extent than the low-fat diet – over a 12-month period.

Because the carnivore diet is a “zero carb” and high protein diet – there’s reason to suspect that it may increase peptide YY concentrations (perhaps significantly) whereby appetite decreases, calorie intake decreases, and weight loss or body composition improvements occurs.

Hormone balance in women

McGrice and Porter (2017) (R) conducted a systematic review of the effects of low carbohydrate diets on hormone profiles in women.

In the review by McGrice and Porter, low-carbohydrate diets were defined as carbohydrate intakes equal to or less than 45% of one’s total macronutrient intake.

Although favorable effects upon hormone balance resulting from low carbohydrate diets in women cannot be generalized to the carnivore diet – it’s possible that some or much of the benefit was due to carbohydrate restriction.

Since the carnivore diet is a “zero carb” diet, it’s possible that this could yield equal or better improvement in hormone balance (for select women) than standard low carb diets.

Ghrelin

Ghrelin is commonly referred to as the “hunger hormone” because one of its primary functions is to stimulate appetite, promote food intake, and fat storage.

The aim of the study was to determine the effect of a meal’s macronutrient composition on post-prandial (post-eating) gut appetite hormones.

Participants in this study received: (1) high carbohydrate (79% of calories from carbs) and (2) high protein (55% of calories from protein) meals – each in a random order.

Results of the study showed that ghrelin suppression was greater after consuming the high protein meal – suggesting that higher protein meals blunt postprandial appetite and enhance satiety.

Furthermore, glucose and insulin spikes were greater following the high carbohydrate meal – suggesting greater fluctuations in glucose, possibly followed by energy crashes (e.g. feeling tired an hour or two after eating).

Although the macronutrient composition of each meal did not affect appetite or subsequent energy intake – this study showed that dietary protein can modulate postprandial ghrelin.

Perhaps over a longer-term, consistent suppression of ghrelin following intake of high protein meals would’ve yielded greater weight loss.

Because the carnivore diet is extremely high protein, it might induce even more substantial ghrelin suppression compared to the high-protein meal tested by Nguo et al.

Overall, it’s very likely that the carnivore diet decreases ghrelin due to consistent consumption of high protein foods – making it easier for carnivore dieters to lose weight.

The objective of the study was to compare the effects of meals with different macronutrient profiles (high protein, high carbohydrate, and high fat) on postprandial satiety and appetite hormone responses.

Results indicated that the postprandial GLP-1 (glucagon-like peptide-1) response was greater after high fat and high protein meals – in both lean and obese men.

The high fat meal was associated with higher postprandial peptide YY concentrations relative to the high carbohydrate meal in obese men.

Since the carnivore diet is high-protein with moderate-to-high fat, it’s possible that some carnivore dieters will experience greater GLP-1 and peptide YY production and ghrelin suppression – relative to had their diets included carbs.

If this is the case, then: satiety should increase, appetite should decrease, food cravings should subside, and successful weight loss is likely.

Because the carnivore diet is extremely high in protein, it’s likely that the favorable effects (reported by Journel et al.) associated with high protein diets become evident in at least a subset of carnivore dieters.

Journel et al. stated that the consumption of a high-protein diet causes the gut to produce different hormones (relative to other diets) including cholecystokinin (CCK) – an appetite that increases “fullness” over the short-term.

Cholecystokinin and other hormones produced following consumption of a high-protein diet have been shown to alter signaling from the vagal nerve to the brain.

This altered signaling (vagal nerve to brain) ultimately modulates neuronal activity and pathways in the brain that regulate food intake – leading to lower rates of food consumption, reductions in body weight, and weight loss.

Lower insulin

It’s logical to suspect that a carnivore diet may be an effective way to reduce insulin and restore insulin sensitivity among persons with insulin resistance.

Lower fasting insulin concentrations and triglycerides were reported among the higher-protein dieters as well.

Because the carnivore diet is very high in protein, and higher protein (over the long-term) is associated with lower insulin concentrations, it’s likely that the carnivore diet may be helpful for restoring insulin sensitivity.

Nutritional deficiencies have been causally implicated in depression and mood irregularities.

Because the carnivore diet consists of animal products with highly-bioavailable nutrients, it’s reasonable to acknowledge that some individuals may experience improvement of nutritional status (relative to their previous diets) while eating carnivore.

For example, if you weren’t eating much vitamin B12 and had a deficiency (even if subclinical), reversing it with higher red meat intake might improve your mood.

If your gene expression reduces or prevents efficient conversion of beta-carotene to retinol (vitamin A), you may have been vitamin A deficient – and correcting this deficiency by eating organ meats (e.g. beef liver) on a carnivore diet should improve your mood.

As was mentioned earlier in the article, the carnivore diet has potential to improve hormone levels.

Hormones that may be modulated on the carnivore diet include:

Satiety hormones (ghrelin, GLP-1, leptin, peptide YY)

Sex hormones (estrogen, testosterone, sex hormone binding globulin)

Stress hormones (cortisol, epinephrine)

Thyroid hormones (T3, T4, TSH)

Assuming the carnivore diet helps improve hormone production and/or balance – this could lead to mood improvements (especially among individuals with uncorrected imbalances).

Food elimination

The elimination of plant toxins, sugars, and other foods to which someone is allergic/intolerant or sensitive (e.g. gluten, lectins, etc.) has potential to modulate: hormones, inflammatory responses, and blood sugar.

Because the carnivore diet is associated with intake of high-protein with moderate fat – and zero carbohydrates, many carnivore dieters will experience weight loss with favorable body recomposition (fat loss/muscle preservation).

The fat loss achieved on a carnivore diet should help reduce inflammation (high body fat induces a chronic inflammatory response) – and this reduction has potential to improve mood.

The combination of weight loss accompanied by favorable body recomposition (fat loss with muscle preservation/gain) might increase confidence, physical attractiveness, and dating/mating opportunities – each of which could independently or synergistically enhance mood.

Medical condition improvement (?)

Anyone with a medical condition who experiences symptom reduction or remission on the carnivore diet will probably end up with a better mood as a result of symptom improvement.

In the event that symptoms and/or symptom “flare ups” decrease with the carnivore diet, it’s logical to suggest that this could yield mood improvement.

Placebo effect

It’s fair to suggest that a subset of carnivore dieters who report mood enhancement after switching to the carnivore diet are experiencing a placebo effect.

Many medical doctors and authority figures actively endorse the carnivore diet – and have suggested that it could improve mood.

Additionally, many anecdotes circulating online within the carnivore community report mood improvement while eating carnivore.

The combination of authority figures (e.g. medical doctors) and members of the carnivore community reporting mood enhancement or stability from carnivore – may lead some new carnivore dieters to expect mood improvements from the diet.

Strong expectation or belief that a carnivore diet will improve mood has potential to (as a standalone) modulate physiology in ways that improve mood or other aspects of health.

Psychiatric disorders

Many people claim to have experienced drastic symptom reduction or complete remission of psychiatric disorders while on the carnivore diet.

Psychiatric disorders that have been anecdotally reported to improve via the carnivore diet include:

Anxiety disorders

Autism spectrum disorder

Bipolar disorder

Major depressive disorder

There are a variety of potential mechanisms by which a psychiatric disorder might improve or remit on the carnivore diet.

Omega-3 fatty acids

Although not all carnivore dieters consume foods that are rich in omega-3 fatty acids, many carnivore dieters do.

If an individual was deficient in omega-3 fatty acids (DHA and EPA) prior to the carnivore diet, reversing this deficiency could account for substantial improvements in psychiatric disorders.

Diets rich in omega-3 fatty acids are associated with lower rates of psychiatric disorders – and less severe symptoms among those diagnosed with psychiatric disorders.

Fatty fish such as salmon, mackerel, herring, and sardines – and shellfish like oysters are extremely high in omega-3 fatty acids.

Fish eggs (roe) from fatty fish like salmon are also packed with omega-3 fatty acids.

Additionally, body recomposition on a carnivore diet might improve energy levels, boost confidence or self-esteem, and enhancephysical attractiveness (such that more dating/mating opportunities become available) – all of which have potential to attenuate symptoms of a psychiatric disorder.

Amino acids

In the event that someone consumed few or zero animal products prior to the carnivore diet – it’s possible that a deficiency in amino acids caused or exacerbated psychiatric symptoms.

Amino acids are referred to as the “building blocks of life” and have many different important functions within the body.

A total of 12 amino acids are synthesized within the body – and the remaining 8 essential amino acids need to be obtained through one’s diet.

A reduction in systemic inflammation, particularly if substantial, could enhance neurotransmitter production and/or attenuate states of neural dysfunction.

Additionally, the elimination of refined sugar might further decrease inflammation and stabilize blood sugar (especially in the context of a zero carbohydrate diet).

Some studies show that high-protein/low-carbohydrate diets are capable of improving hormone balance – leading some to hypothesize that complete elimination of carbs may provide even greater benefit.

In sum, there are several mechanisms (inflammation reduction, blood sugar stabilization, hormone optimization) by which the elimination of certain foods and/or compounds on a carnivore diet could decrease symptoms of psychiatric disorders.

For some individuals, the carnivore diet may help to optimize and/or balance hormone levels within the body to counteract symptoms of psychiatric disorders such as: anxiety, bipolar disorder, and depression.

Research suggests that a high-protein, low-carbohydrate diet (like the carnivore diet) can modulate appetite-related hormones such as: ghrelin, leptin, GLP-1, and peptide YY.

Interestingly, concentrations of the aforementioned appetite hormones may also influence the severity of psychiatric symptoms.

Some studies show that a high-protein, low-carbohydrate diet (like the carnivore diet) may improve the balance between concentrations of sex hormones like testosterone and estrogen in women. (R)

Additionally, the elimination of foods with goitrogenic compounds (e.g. broccoli, kale, etc.), soy products, and excessive quantities of iodine (such as from seaweed) – could improve thyroid function and production of thyroid hormones (T4, T3, TSH).

Increasing the production of key thyroid hormones could certainly improve the mood of an individual with psychiatric symptoms attributable to clinical or subclinical thyroid dysfunction.

Cholesterol & IGF-1 normalization

It is known that some diets (e.g. vegan) may lead adherents to exhibit abnormally low concentrations of cholesterol and IGF-1.

Both low cholesterol and low IGF-1 are linked to cognitive dysfunction and psychiatric symptoms like depression and suicidality. (R1, R2, R3)

Because the carnivore diet provides plenty of cholesterol and IGF-1 from animal products, it’s reasonable to suspect that this should substantially increase concentrations in persons with suboptimal levels.

Increasing cholesterol and IGF-1 to moderate levels (from previously deficient levels) has potential to mitigate psychiatric symptoms in a subset of persons on the carnivore diet.

Medical condition improvement

Many psychiatric disorders have bidirectional relationships to other medical conditions – meaning the pathophysiology of each condition affects symptoms/severity of the other.

For example, in someone with both an autoimmune disease and a psychiatric disorder, flare-ups associated with their autoimmune disease may trigger a worsening of their psychiatric disorder (and vice-versa).

In this example, if the carnivore diet decreases symptoms of the autoimmune disease, then this could certainly prevent flare-ups associated with the psychiatric disorder.

Most chronic medical conditions are highly stressful, and if better controlled via the carnivore diet, psychiatric disorder symptoms and total psychological stress should decrease.

Placebo response

A paper by Marchesi et al. (2013) estimates that a placebo effect accounts for 67% of the total antidepressant effect observed in patients treated with antidepressant medications. (R)

Certain people are more prone to the placebo effect than others – but likelihood of a successful placebo effect increases with authority figures endorsing the intervention.

As I’ve mentioned earlier in this article, the carnivore diet is suggested by several medical doctors online as a potentially useful intervention for psychiatric disorders.

Factor in the countless testimonials within the carnivore community regarding mood improvements and/or psychiatric disorder cures – and we’ve set a pretty good stage for a placebo effect.

But likelihood of the placebo further increases if we think of the fact that people transitioning to carnivore: (1) might read potential mechanisms by which the diet can enhance mood and (2) will likely drastically alter their food choices from a prior diet (a major change).

The combination of aforementioned variables could strengthen one’s conviction that the carnivore diet will attenuate psychiatric symptoms – and as a result of this conviction or belief, physiology changes in a way that actually attenuates the psychiatric symptoms.

Reversal of deficiencies (amino acids & vitamins)

Although some question whether the carnivore diet is nutritionally sufficient, many moderate-term and long-term carnivore dieters claim that their bloodwork (i.e. test labs) show zero nutrient deficiencies.

It is possible that individuals who transition from a poorly-planned diet of any type (e.g. ketogenic, omnivorous, vegetarian, vegan diet) could experience health improvement on the carnivore diet via reversal of deficiencies in amino acids and vitamins.

Within the carnivore community, there are many former vegans (some of whom probably followed a poorly-planned vegan diet and/or failed to supplement with adequate vitamin B12) who report dramatic health improvement on the carnivore diet.

A poorly-planned diet and/or gene expression that impairs absorption of plant-based vitamins (such as interfering with conversion of beta-carotene to retinol) – might have resulted in a deficiency.

Since the carnivore diet provides all 20 amino acids and highly bioavailable nutrients that may have been deficient on a vegan diet like vitamin B12 and retinol (via organ meats) – health improvements will occur in persons with underlying deficiencies.

The same nutrients that are easily attained and highly bioavailable on a carnivore diet are often deficient in vegan dieters. These nutrients include:

Carnitine

Carnosine

Cholesterol

Choline

Creatine

DHA/EPA

Glycine

Iodine

Iron

Taurine

Vitamin A

Vitamin B2

Vitamin B3

Vitamin B6

Vitamin B12

Vitamin D3

Zinc

Restoring levels of these nutrients (from a deficient state) and, in some cases, increasing intakes of these nutrients above the RDA can improve many aspects of health including: cognitive performance, physical performance, sex drive, and mood.

Skeletal health

Many individuals have reported improvements in bone health and muscle mass while on the carnivore diet.

A well-planned carnivore diet may improve bone mineral density, muscle mass, strength, and help prevent or reverse osteoporosis and sarcopenia – largely due to high protein intake.

The carnivore diet is extremely high in bioavailable animal proteins that contain all 20 essential amino acids necessary to build muscle and prevent muscle wasting.

There’s no evidence that high protein intake is detrimental to bone mass and strength – in the context of adequate calcium and vitamin D intake.

Higher frequency of meat intake in Chinese women was associated with lower rates of osteoporosis (a medical condition in which bones become brittle from loss of tissue). (R)

Overall, assuming that adequate vitamin D and calcium are attained from the carnivore diet (or via supplementation during the carnivore diet) – high protein intake from the carnivore diet will likely enhance musculoskeletal health.

Skin health (acne, eczema, etc.)

Anecdotes suggest that skin appearance and skin conditions such as acne and eczema can improve on the carnivore diet.

Mechanisms by which skin health could improve on carnivore include: elimination of foods/compounds (associated with allergies/sensitivities); increasingintake or absorption of certain nutrients; elimination of hyperglycemic carbs; and reduction of total energy intake.

Eliminating food allergies

Individuals with food allergies or sensitivities commonly experience skinrashes and/or breakouts after consuming the food to which they are allergic.

Many people who haven’t been formally evaluated for allergies or sensitivities (e.g. by an allergist) will continue consuming foods to which they have an allergy or sensitivity – resulting in ongoing skin problems.

Some people have speculated that increased intake of animal fats and/or reversal of nutrient deficiencies (e.g. zinc, vitamin B12, etc.) may contribute to reported skin improvement on a carnivore diet.

Elimination of carbohydrates

The carnivore diet is a “zero carb” diet in which no carbohydrates are consumed – only protein and fat.

The complete elimination of dietary carbohydrates (especially refined and hyperglycemic carbs) on a carnivore diet, may effectively reduce the occurrence of acne and improve skin health. (R)

Kucharska et al. propose that consumption of hyperglycemic carbohydrates can elevate insulin levels which in turn stimulates androgen secretion to increase production of sebum, playing a role in the pathogenesis of chronic acne.

Dairy restriction or avoidance

It should be stated that many individuals abstain from dairy products on the carnivore diet and stick to consuming just meat and/or fish.

The restriction of dairy products is suggested by Romańska-Gocka et al. (2016) as a potential dietary intervention for acne. (R)

Avoiding or limiting dairy on the carnivore diet might be reason as to why acne and/or skin health improve during carnivore (for a subset of persons). (R)

Calorie reduction

Reducing/restricting calories on the carnivore diet is relatively effortless because nearly all of the foods consumed will be high-protein; protein is the most satiating macronutrient.

Energy restriction (i.e. calorie reduction) has been proposed as a potentially-useful dietary intervention for the management of acne.

Papers by Melnik (2012) and Romańska-Gocka et al. (2016) agree that restriction of calories may modulate mTORC1 (nutrient-sensitive mammalian target of rapamycin complex 1 kinase) in a way that could reduce acne. (R1, R2)

Assuming your caloric intake decreases during the carnivore diet (relative to your previous diet) – this could account for any favorable changes in acne breakouts and skin health.

Thyroid function

Although most diets probably aren’t interfering with thyroid function, some individuals may endure self-inflicted thyroid dysfunction via their food choices.

Among individuals with clinical or subclinical thyroid dysfunction as a result of food choices, it’s possible that the carnivore diet may restore normal thyroid function.

Restoration of normal thyroid function via the carnivore diet should help improve or optimize concentrations of thyroid hormones such as T4, T3, and TSH.

A research paper by Bajaj et al. (2016) indicates that while thyroid dysfunction is most attributable to genetics (70% of risk) – environmental toxins may increase risk of and/or provoke thyroid dysfunction.

Vitamin B12 deficiency. It has been reported that vitamin B12 deficiencies have been involved in autoimmune thyroiditis. If one’s diet prior to carnivore was deficient in vitamin B12 – this deficiency could’ve induced or exacerbated autoimmune thyroiditis.

Bajaj et al. (R) goes as far as to give some recommendations to patients with hypothyroidism:

Since the carnivore diet: (1) is devoid of raw cruciferous vegetables and other plant compounds that could interfere with thyroid function; (2) may contain highly bioavailable thyroid-boosting compounds (tyrosine, zinc, iron, etc.); and (3) could reverse a vitamin B12 deficiency – it’s possible that some individuals will report improvements in thyroid function while eating carnivore.

Because the carnivore diet is high/ultra-high protein and can be fairly repetitive in food choices – many carnivore dieters will naturally eat less (i.e. consume fewer calories than pre-carnivore).

Consumption of fewer calories on the carnivore diet (relative to a previous diet) will result in weight loss.

Moreover, the specific type of weight loss that occurs on a carnivore diet (fat loss with muscle preservation) will probably be perceived as superior to weight loss that occurs on lower protein diets (fat and muscle loss).

Lower protein diets may leave someone with a “skinny fat” appearance after weight loss in which their body appears skinny with high fat and little muscle.

Since the carnivore diet is high/ultra-high in protein, and protein: (1) is difficult for the body to store as fat and (2) promotes lean mass preservation – many carnivore dieters will report weight loss with favorable body recomposition.

What are the most likely reasons a carnivore diet is beneficial?

It’s impossible to know exactly where a majority of the benefits are coming from on a carnivore diet for every single person – this would require a case-by-case analysis.

However, my guess is that most people on a carnivore diet who report health improvement(s) are benefitting from a combination of: calorie reduction (relative to one’s previous diet) and corresponding weight loss with body recomposition (fat loss plus muscle gain).

1. Calorie reduction or restriction.

Upon transitioning to a carnivore diet, it’s very likely that you’ll decrease your total daily calorie intake relative to your previous diet – even if you aren’t consciously aware of it.

Most people don’t track their calories closely and, upon transitioning to carnivore diet, some individuals will mistakenly assume they’re eating a significantly greater number of calories per day relative to pre-carnivore.

Animal products like ground beef, organ meats, and chicken are high protein foods that are difficult to overeat.

Due to the consumption of high-protein animal products, it’s easy to be satiated with fewer calories.

What’s more, protein is the most thermogenic macronutrient and is difficult for the body to store as fat.

As a result, you’ll burn more calories per day consuming an ultra-high protein diet relative to equal-calorie diets with lower protein amounts.

Moreover, many carnivore dieters consume the same or similar foods daily – especially when starting the diet.

Consuming the same foods regularly (i.e. eating a familiar, repetitive diet) is associated with appetite reduction and lower calorie intake.

Predictably, many carnivore dieters will end up reducing or restricting calories on a carnivore diet – while simultaneously burning more calories (due to the slight metabolic advantage of high protein intake) relative to their previous diets.

Note: Not everyone on the carnivore diet will have reduced or restricted calories relative to pre-carnivore. That said, most carnivore dieters will decrease calorie intakes and/or increase energy expenditure due to high-protein contents of their food (leading to quicker satiety and increased metabolism due to the thermic effect of protein).

2. Weight loss & body recomposition.

As was mentioned, many people on the carnivore diet will reduce or restrict calories (relative to pre-carnivore) even if they aren’t consciously aware of the reduction/restriction.

Because most foods consumed on the carnivore diet are extremely high in protein, it’s difficult to overeat – as protein is the most satiating macronutrient.

Additionally, high protein intake on a carnivore diet causes the body to burn a slightly greater number of calories per day (relative to equal-calorie diets lower in protein) due to the thermic effect of protein.

More specifically, the exerts more energy (i.e. burns more calories) metabolizing proteins relative to carbohydrates and fats.

The potential combination of variables: (1) caloric reduction/restriction; (2) high satiation; and (3) increased metabolism – can lead to effortless weight loss.

Cascade effect. A cascade effect is formally defined as “an inevitable and sometimes unforeseen chain of events due to an act affecting a system.”

Due to the combination of calorie reduction and weight loss (with body recomposition), carnivore dieters notice improvements in all aspects of health.

The combination of calorie reduction and weight loss (while on a carnivore diet) may:

Attenuate medical conditions

Decrease inflammation

Enhance mood and cognition

Increase energy and motivation

Improve insulin sensitivity

Lower blood pressure

Optimize hormone levels

Stabilize blood glucose

Regulate immune function

Reverse hyperlipidemia

Any improvement in one aspect of health via the carnivore diet may facilitate improvement in another aspect due to multi-directional relationships between biological systems.

For example, if the carnivore diet leads to weight loss which improves hormone production – the hormone improvements have potential to enhance mood, energy, motivation, and cognition.

Essentially, what I’m arguing is that the combination of calorie reduction with weight loss is the biggest force multiplier by which the carnivore diet enhances health.

Other ways the carnivore diet may improve health

Although calorie reduction and weight loss are probably responsible for a majority of the health benefits on a carnivore diet, these are not necessarily the means by which all carnivore dieters derive benefit.

For example, someone who previously consumed a high-protein diet and is in good shape might not alter calorie intake much nor experience weight loss or change in body composition – after transitioning to the carnivore diet.

In this case, reported benefits from the carnivore diet could be attributable to: a placebo effect, modulation of nutritional status, altering amino acid intake, or elimination of specific foods/compounds.

Amino acid intake: The carnivore diet contains all 20 essential amino acids in a bioavailable format. Some individuals may report health improvement on the carnivore diet as a result of increased amino acid intake (possibly by reversing deficits or providing extra – some people function better with higher intakes).

Blood sugar stabilization: The high-protein, moderate-fat carnivore diet has potential to stabilize post-prandial blood sugar more effectively than other diets. Stabilization of blood sugar may improve various aspects of health and functioning.

Gut microbiome alteration: Although there’s no conclusive evidence that altering the gut microbiome directly improves health – it’s a possibility that warrants consideration. Because some individuals report improved gut microbiome composition on a carnivore diet – it’s possible that this is a mechanism by which benefits are attained.

Hormone modulation: The carnivore diet will likely modulate production of various hormones throughout the body. For some individuals, modulation to hormones like: thyroid (T4, T3, TSH); IGF-1; testosterone; and estrogen – could be how the diet favorably improves aspects of one’s health.

Mild nutrient deficit: Some scientists believe that the carnivore diet is beneficial for some individuals with autoimmune disorders by way of inducing mild nutrient deficiencies. The mild nutrient deficiencies are thought to suppress (overactive) immune responses to attenuate symptoms.

Placebo effect: A placebo response to the carnivore diet cannot be discounted. Authority figures (e.g. medical doctors) promote the diet; the diet involves drastic elimination of most foods relative to a prior diet; and carnivore support groups have cropped up on the internet (mostly embellishing positive outcomes – and scrutinizing negative outcomes) – all of which increase likelihood of a placebo response in susceptible persons.

Carnivore diet: Medical conditions & symptoms, health effects

Below is a compilation of medical symptoms and medical conditions (that reportedly improved) – and other health benefits documented within anecdotes from carnivore dieters on MeatHeals.com. (R)

Calcium-D-glucarate: This supplement may support kidney and liver function while on the carnivore diet via enhancement of the Phase II detoxification pathway. Some sources suggest that taking calcium-d-glucarate prior to consuming cooked meat may protect against exposure to toxins like benzopyrene and polyaromatic hydrocarbon compounds.

Collagen: Paul Saladino takes 10 to 20 grams of collagen per 100 grams of protein consumed to help balance out methionine.

Glutathione: Some people may do better with extra glutathione in the form of a supplement on a carnivore diet. Glutathione is a master antioxidant that helps decrease oxidative stress.

Fish oil: If you’re consuming fish rich in omega-3 fatty acids, there’s no need to supplement with fish oil. That said, some people do better with more fish oil than they can get from fish – and like to supplement. Be very cautious of storage and the specific product you order (to avoid rancidity).

Folate: Some individuals may end up with a folate deficiency on a carnivore diet. To avoid a folate deficiency – you may want to supplement.

Glycine: Supplementation with glycine can balance the high methionine intake on a carnivore diet. If deficient in glycine, this may interfere with our body’s ability to produce collagen and glutathione (a master antioxidant). Paul Saladino takes 10 grams of glycine per day – and says powdered forms are sweet (taste like sugar).

Krill oil: This is an alternative to fish oil that provides omega-3 fatty acids with substantially greater bioavailability. If you don’t consume seafood – you may want to supplement with omega-3s.

Manganese: This is a trace mineral necessary for proper nervous system functions, formation of collagen, and protection against oxidative stress. Some people may want to supplement.

Magnesium citrateormagnesium glycinate: For some individuals, it’s difficult to get adequate magnesium on a carnivore diet. Furthermore, the carnivore diet might increase production of stress hormones (e.g. epinephrine, norepinephrine, etc.) for some people. Supplementing with magnesium citrate or glycinate should prevent a magnesium deficiency, improve sleep, and decrease stress hormones.

NAC: This is a supplement that acts as a precursor to glutathione. Supplementing with NAC may increase concentrations of glutathione, a master antioxidant within the body.

Pasture-fed liver: If you have a tough time finding and/or consuming grass-fed liver from pasture-raised, grass-fed cows, you may want to supplement. Although I recommend eating actual liver (instead of supplementing) – supplementation can help provide nutrients that you would otherwise be missing (e.g. Vitamin A) if you forgo liver consumption.

Potassium: The carnivore diet doesn’t provide much potassium. Although not everyone on the carnivore diet needs to supplement with potassium – many people will function better with a potassium boost.

Himalayan Salt or iodized salt: Salt is necessary for many biological functions. If you’re getting adequate iodine (from diet) you may want to use Himalayan salt (devoid of iodine). However, if your diet is lacking in iodine, consider using iodized salt with the carnivore diet to prevent a deficiency.

Vitamin A: No need to supplement with vitamin A if you’re eating necessary organ meats (e.g. beef liver). However, if you are avoiding organ meats – vitamin A is something to supplement with.

Vitamin C: Although carnivore dieters have argued that vitamin C needs are reduced on the carnivore diet, thereby making them immune to scurvy – others would rather supplement to avoid the risk.

Vitamin D: Vitamin D can be attained from adequate UVB sunlight exposure and various foods. However, if you don’t get much sun exposure – you may want to supplement with vitamin D.

Vitamin E: It’s generally difficult to get adequate vitamin E on a carnivore diet. Supplementation may be necessary if you want to avoid a deficiency.

Vitamin K2: This is a fat-soluble vitamin that reduces calcification of blood vessels. Some individuals may be deficient on a carnivore diet.

Note: Although your bloodwork may show adequate levels of these vitamins/minerals, it’s important to realize that blood levels are not always what should be assessed – especially for calcium and magnesium. (R)

Intracellular stores of these minerals may be depleted in the context of normal blood levels – leading to a deficiency without your awareness.

Foods for a carnivore diet

Included below is a list of foods/snacks that are compliant with a carnivore diet and can be ordered online.

Carnivore diet FAQ (Frequently Asked Questions)

Included below are frequently asked questions about the carnivore diet – along with answers.

steak on the grill

Understand that answers to these questions are only my opinion – and should not be substituted for professional medical and/or nutritional advice.

Should you try the carnivore diet?

It’s your choice. If you’re dissatisfied with how you feel on your current diet – and are intrigued by a carnivore style of eating – have at it.

The carnivore diet is relatively easy for most people to follow – especially over a short-term.

Before trying a carnivore diet, it’s recommended to discuss it with a medical doctor to ensure that the diet won’t worsen any preexisting medical condition(s).

Which populations might be best suited to try a carnivore diet?

Based on literature and anecdotes, below are some conditions and/or types of people who may derive more benefit from the carnivore diet than others.

Gastrointestinal disorders. If you have a gastrointestinal disorder and conventional medical recommendations have failed to improve your condition – it may be worth trying a carnivore diet. Some studies suggest that subsets of patients with diverticulitis may benefit substantially from eliminating fiber from the diet.

Inability to stick with other diets. The carnivore diet is extremely easy to follow and effective for weight loss because it is high in protein and contains zero hyperpalatable foods. If you find yourself unable to stick with other diets (e.g. keto, vegan, etc.) – you may have more success with carnivore.

Obese, overweight, skinny fat. The carnivore diet is high or ultra-high in protein – and often repetitive (in terms of food choices). This combination tends to suppress appetite and increase satiety better than other diets – leading to successful weight loss. Additionally, the body has a difficult time storing protein as fat – and instead uses the protein to preserve muscle – ultimately changing body composition for the better.

Mental health problems. Of all anecdotes reported on MeatHeals.com, the greatest number of improvements were reported in the category “mental health.” Anecdotes document the carnivore diet as having cured or reduced symptoms of conditions like: autism spectrum disorder; anxiety disorders; bipolar disorder; and major depressive disorder.

Can health benefits of the carnivore diet be attained with another diet?

It depends upon the individual. For many people, similar health benefits derived from the carnivore diet can be attained with other diets. However, there are some people for whom the carnivore diet may be an optimal choice.

As I’ve suggested, the combination of caloric reduction andweight loss with favorable body recomposition (fat loss with muscle preservation or gain) – during the carnivore diet – is likely culpable for eliciting a beneficial “cascade effect” wherein all aspects of one’s health improve while eating carnivore.

Assuming I engineered a diet that matched total daily calorie intake on carnivore – and also matched dietary protein intake to that of carnivore – there shouldn’t be any significant differences in weight loss or body recomposition.

On a carnivore diet, I could devise a plan wherein someone consumes 250 grams of protein (1000 calories) and 111.11 grams of fat (1000 calories) for a total of 2000 calories per day.

On an omnivorous diet, I could devise a plan wherein someone consumes 250 grams of protein (1000 calories); 150 grams of carbohydrates (600 calories); and 44.44 grams of fat (400 calories) for a total of 2000 calories per day.

If most of the beneficial effects of the “carnivore diet” are mediated by weight loss and/or body recomposition, then the second diet should be as effective as the first diet.

Unless you’ve previously tried a high-protein omnivorous diet with fruits, vegetables, whole grains – and simultaneously without hyperpalatable (high in sugar, fat, and salt) “junk foods” – without success, it may not be the best idea to jump on the carnivore bandwagon.

I suspect that if we were to conduct a randomized, double-blind, controlled experiment – carnivore diet vs. an omnivorous diet while controlling for calorie intake and percentage of calories from protein – health outcomes would be similar in most people.

Is a carnivore diet safe for humans long-term?

Unknown. As of current, the carnivore diet hasn’t been evaluated long-term in humans for safety.

For this reason, if you’re already healthy and feel good on an omnivorous diet that includes whole grains, fruits, and vegetables – it may not be the smartest idea to follow a carnivore diet over a long-term.

However, if your quality of life is low and/or your health is already at risk due to obesity (or another medical condition) – and the carnivore diet substantially improves your health – it’s probably better to stick with carnivore long-term.

In this case, based on the overwhelmingly negative results – it makes sense to discontinue carnivore.

Risk of disease, all-cause mortality, lifespan

Assuming that your health substantially improves (like Scenario A) on the carnivore diet, then it makes sense to continue the diet (or a variation of it) for the long-term.

Why? Because if you’re suffering from obesity and/or another medical condition that you can only control with the carnivore diet – then continuation of the diet is obviously your best bet.

For example, if you’ve tried many different diets and continue to yo-yo back up to 40% body fat – this amount of body fat alone will raise your risk of disease and all-cause-mortality – and will likely shorten your healthspan and lifespan.

If you’re able to drop from 40% body fat to 15% body fat with the carnivore diet and maintain your new body fat percentage – it makes sense to continue the carnivore diet.

Why? Because the lower body fat is the force multiplier that will decrease your risk of disease, all-cause-mortality, and should extend both healthspan and lifespan.

If body fat and weight are most culpable for your health issues (e.g. type 2 diabetes, carpal tunnel syndrome, hormone imbalances, inflammation, depression, fatigue, etc.) – targeting these with any strategy that works (e.g. the carnivore diet) is recommended.

Certain individuals may opt to utilize a strict carnivore diet for a limited duration with the intent of weight loss and body fat reduction.

Once weight loss and body fat reduction are achieved, adding various foods back into one’s diet may be a smart idea – so long as they don’t: (1) trigger binge eating or food cravings; and (2) cause adverse reactions (e.g. allergies).

What if you’re already in good health?

If you’re already in good health (non-obese, normal body fat, no preventable medical conditions) – it’s probably smarter to follow an omnivorous diet over the long-term.

Why? Because the carnivore diet hasn’t been extensively studied over a long-term in modern populations.

The old adage “if it ain’t broke, don’t fix it” applies to diet.

If your relatives (siblings, parents, grandparents, etc.) have long healthspans and lifespans on varied, omnivorous diets – there’s probably no need to reinvent the wheel and follow a carnivore diet.

Moreover, although the studies are correlational, nearly all data suggest that higher intakes of fruits, vegetables, nuts/seeds, whole grains, and fiber – are associated with greater longevity and lower risk of death – especially in conjunction with regular exercise and normal body fat. (R1, R2)

Additionally, most correlational data suggest that higher intakes of red meat and saturated fat are associated with shorter lifespan and greater risk of death – especially in conjunction with sedentary lifestyle and elevated body fat.

Everything considered, there are no data to suggest that a long-term carnivore diet enhances health.

Sure we can reference the Greenland Eskimos as being healthy on the carnivore diet – but characteristics of this tribe probably aren’t consistent with your average carnivore dieter.

The Greenland Eskimos: (1) were extremely active (sometimes exercising between 24 and 36 hours with no rest); (2) lived in harsh conditions (cold, lack of sunlight); (3) intermittently fasted (consuming as much as possible – then going without food for long periods of time); and (4) had low body fat (many starved to death).

Overall mortality of these Eskimos was nearly double that of the Danish population – and life expectancy was around 10 years shorter than the Danish population.

The increased mortality and shorter lifespan in Greenland Eskimos may have been attributable to other factors (e.g. harsh living conditions, lack of sunshine, lack of medical care, etc.) – but there’s absolutely zero evidence to suggest that a carnivore diet is somehow “healthier” than a mixed, omnivorous diet.

Although epidemiological data do not establish causation – and may be suboptimal for creating dietary guidelines – they’re currently the only data we have.

Moreover, epidemiological data are able to highlight an evolutionary stable dietary strategy for many long-lived, healthy humans.

The evolutionary stable strategy that seems to be working for many humans with long healthspans and lifespans is a diet that includes: vegetables, fruits, whole grains, nuts/seeds – in addition to meat and seafood.

Does this mean that a long-term carnivore diet is unhealthy? Not necessarily. It just means that we know, at the very least, that including: vegetables, fruits, whole grains, and nuts/seeds in the diet over a long-term – seems to be healthful (and probably isn’t harmful) for most people.

I know it’s tempting to think that: (1) the carnivore diet is some “magic bullet” for health problems; (2) you’re smarter or blessed with unique diet insight (relative to others); and (3) the carnivore diet is healthier than all other diets – but this probably isn’t the case.

If the carnivore diet improves your health over a long-term, then by all means, keep following it.

But if your health declines on the carnivore diet and/or you were already in good health pre-carnivore then I wouldn’t recommend carnivore for the long-term.

Is it better to eat a nose-to-tail style carnivore diet?

Unknown. As of current, it remains unknown as to whether it’s healthier to eat a nose-to-tail (NTT) style carnivore diet relative to a non-nose-to-tail style (non-NTT) carnivore diet.

If I were to speculate as to whether a nose-to-tail style carnivore diet (that includes organ meats, entrails, etc.) is healthier than a non-nose-to-tail (no organ meats) style carnivore diet – I’d side with the former (nose-to-tail).

Organ meats are extremely nutrient-dense, containing vitamins in quantities that are unmatched by a non-nose-to-tail style carnivore diet.

For this reason, I suspect that many individuals on non-nose-to-tail style carnivore diets experience deficiencies in various nutrients that nose-to-tail style dieters do not experience.

If I were to try the carnivore diet, I would adhere to a nose-to-tail style of eating in order to avoid or reduce the risk of developing potentially-serious nutrient deficiencies (e.g. vitamin A; calcium; folate; copper; et al.) and imbalances (e.g. methionine/glycine ratio), etc.

This does NOT mean that I think a non-nose-to-tail style carnivore diet is automatically inferior, unhealthy or suboptimal relative to the nose-to-tail style.

It just means that I’d rather take some precaution (via consuming organ meats) to minimize risk of nutrient deficiencies and other imbalances within the body – because the consequences could be serious, particularly if undetected or unaddressed over a long-term.

Shawn Baker’s thoughts…

That said, Shawn Baker makes some good points as to why a nose-to-tail style carnivore diet may be unnecessary, one of which is the fact that many people are getting good results (i.e. experiencing health benefits) without the nose-to-tail style eating. (R)

Shawn points out that many people on non-nose-to-tail style carnivore diets aren’t reporting vitamin deficiencies or homocysteine abnormalities (that some have linked to imbalances in methionine/glycine ratio) with consumption of muscle meat.

Shawn also mentions that humans may not have evolved eating many organ meats (as evidenced by the fact that many people dislike their taste) – and further states that nutrient deficiencies might be less likely to occur in the absence of carbohydrate intake.

Paul Saladino’s thoughts…

In response to Shawn Baker, Paul Saladino states that homocysteine isn’t a great indicator of methionine/glycine ratio or glycine adequacy.

Paul further notes that although glycine can be manufactured by the body, it is frequently not manufactured in adequate quantities due to demands.

A key function of glycine is to buffer excess methyl groups from molecules like methionine in the methylation cycle.

Diets with a lot of muscle meat substantially increase methionine and Paul argues that this will use up all glycine stores.

If we fail to replenish deficient glycine stores, Paul suggests that we may be unable to manufacture proteins that use glycine such as glutathione and collagen. (R)

Studies in rodents emphasize the importance of adequate glycine in the setting of high methionine diets (like the carnivore diet).

Although glycine research in rodents doesn’t necessarily apply to humans, there’s reason to suspect that it could.

Paul also claims that if carnivore dieters don’t consume liver, they’ll be at high risk of deficiencies in vitamin A, folate, biotin, omega-3 fatty acids, and copper.

If you avoid organ meats on the carnivore diet, Paul Saladino recommends close monitoring of the aforementioned potential deficiencies.

Vitamin A. There’s little vitamin A in muscle meat and some in eggs (which are consumed on the carnivore diet). However, there’s a substantial amount of vitamin A in liver. According to Paul, consumption of meat alone will yield a vitamin A deficiency.

Copper. Muscle meat is high in zinc and low in copper. A significant imbalance in zinc and copper can yield a copper deficiency accompanied by serious neurologic symptoms.

My thoughts…

I side with Paul Saladino in his recommendation of a nose-to-tail style carnivore diet because I think it’s better to be safe than sorry – especially when the consequences of a nutrient deficiency or imbalance could inflict permanent damage.

However, my hypotheses regarding why I think some people are “getting good results” with a non-nose-to-tail style carnivore diet include:

Preexisting nutrient stores within the body. It may take awhile for a deficiency to manifest after transitioning to carnivore – particularly in overweight and obese individuals.

Hormetic effects. There may actually be a more pronounced hormetic effect on a non-nose-to-tail style carnivore diet than nose-to-tail due to mild nutrient deficiencies. In other words, low intakes of certain nutrients might induce activation of endogenous protective responses within the body to improve health.

Placebo (?): Some individuals might subjectively perceive that they are functioning “better” on a carnivore diet with subclinical nutrient deficiencies – despite the fact that, objectively speaking, decline is apparent. In other words, some intelligent people may appear to function well on the carnivore diet – in spite of nutrient deficiencies.

I should also mention that the Greenland Eskimos, a healthy raw carnivore community, preferred to eat muscle meats, not much fat, and organs only when starving – supporting the idea that it may be possible to function without organ meats.

What would I recommend instead of the carnivore diet?

To be clear, I’m NOT “anti-carnivore diet” if someone finds it sustainable and health-enhancing over a long-term.

When it comes to following a diet, you should focus on 2 things: (1) health impact and (2) adherence.

If a diet is detrimental to your health and/or you’re unable to stick with it over the long-term – I wouldn’t recommend it.

The ideal diet should be considered: (1) nourishing, health-enhancing (or health-neutral) and (2) easy to adhere to over a long-term.

Health effects: An ideal diet should help you maintain a healthy body weight and body fat percentage – all while providing adequate nutrition. It should not include foods associated with allergies.

Adherence: The problem with most diets is that people aren’t able to adhere to them for a long-term. The result? They end up regaining weight, body fat and/or their health declines.

Additionally, I recommend analyzing the healthspans and lifespans of your grandparents – and reflecting upon their diets.

Assuming they consumed omnivorous diets and had favorable healthspans and lifespans – it doesn’t make logical sense to jump ship to an extreme diet like carnivore, keto, raw vegan, etc., especially for the long-term.

On the other hand, if you have a family history of short healthspans and lifespans, it may be worth investigating and/or experimenting with dietary changes in effort to counteract this trend like carnivore, keto, vegan, etc. – along with lifestyle modifications.

Eliminate hyperpalatable foods. Many people blame “sugar” in foods for cravings, but it’s really the combination of high sugar, high fat, and/or high salt altogether. This combination stimulates reward centers in the brain and causes cravings. Discontinuing consumption of donuts, Oreos, chips, and other heavily processed snacks is probably smart.

Avoid allergy-provoking foods. If you’re allergic to foods – don’t eat them. If you’re sensitive to foods – don’t eat them. Talk to an allergist if you want to be tested for various allergies.

Eat nutrient-dense foods. Consume foods with high nutrient-density such as to avoid deficiencies. If you’re unable to get nutrients from a certain food (e.g. vitamin A from carrots) due to a conversion problem – you can try liver or supplementation.

Adequate protein. The carnivore diet is high in protein – which is likely the primary reason it effectively suppresses appetite, preserves muscle, and enables relatively effortless weight loss. To achieve the same effects on a standard omnivorous diet – ensure that your intake of protein remains high (e.g. 1 gram per pound of body weight or more). Grass-fed beef and/or wild-caught fish are good sources of protein because they contain all essential amino acids and are high in omega-3 fatty acids.

Eat enough fat. At the very least, consume 20% of calories from fat. Lack of dietary fat interferes with hormone function and may increase appetite.

Vegetables & fruits. Are vegetables and fruits evil? No. Consuming a variety of vegetables and fruits each day will help you meet micronutrient needs. Moreover, vegetables and fruits contain fiber which can help suppress appetite.

Intermittent fasting (optional). It’s up to you as to whether you want to practice intermittent fasting. There’s no need to intermittently fast if you’re already at a healthy body fat percentage and good weight. If you’re going to intermittently fast – research suggests it’s better to stop eating earlier in the evening relative to postponing breakfast. Why? Insulin sensitivity drops at night due to effects of the circadian rhythm-mediated melatonin release.

Other frequently asked questions (FAQs)

Included below are more frequently asked questions associated with the carnivore diet.

Does the carnivore diet cause vitamin C deficiency?

Probably not. Research suggests that there’s some vitamin C in carnivore diet foods like meat and fish.

In studies that analyzed 2 explorers (on the carnivore diet for 1-year) and Greenland Eskimos (lifelong carnivores), scurvy – a disease resulting from vitamin C deficiency – did not occur, suggesting that vitamin C levels were not clinically deficient.

The notion that there is inadequate vitamin C in meat to prevent scurvy was derived from the inability of meat to prevent scurvy in guinea pigs.

There are numerous problems with drawing conclusions from a guinea pig study in which they consumed meat, including: (1) guinea pigs are herbivores (so dislike meat) and (2) the meat was not tested for vitamin C content. (R)

Here are measurements of vitamin C levels in grain and grass-finished beef. (R)

According to the carnivore community on Reddit, modern examples of scurvy are primarily happening in people eating standard diets with packaged and takeout foods.

People consuming fresh beef and/or organs (e.g. adrenal gland, brain, spinal cord) on the carnivore diet do not seem to suffer from scurvy.

Research compiled by Amber O’Hearn indicates that, even on a diet of just fresh muscle meat, vitamin C deficiency does NOT occur.

Although the small quantity of vitamin C consumed on a carnivore diet may seem inadequate, it is hypothesized that, in the absence of carbohydrates, vitamin C needs significantly decrease.

Why? Many speculate that because glucose is structured similarly to vitamin C, the two compete with each other for glucose transporters. (R1, R2)

If there’s an abundance of glucose, the glucose may interfere with the uptake and absorption of vitamin C via competition at glucose transporters. (R1, R2, R3)

For this reason, it is thought that when glucose increase (such as occurs with high carbohydrate intake), vitamin C isn’t efficiently transported and absorbed – so needs increase.

Conversely, it is thought that when glucose concentrations decrease (such as occurs with zero carb, carnivore diets), vitamin C is efficiently transported and absorbed so needs decrease.

In other words, the hypothesis is as follows: lower glucose intake yields more efficient vitamin C transport and absorption (via glucose transporters) – such that vitamin C requirements may decrease on a lower glucose diet like carnivore.

There are compensatory mechanisms activated when vitamin C is low that are also triggered by low-carbohydrate diets – possibly reducing vitamin C requirements in lower carb conditions.

High levels of vitamin C might be detrimental in low-carbohydrate conditions.

What about deficiencies in calcium, magnesium, and potassium?

Some speculate that, in the absence of carbohydrates (glucose), needs for essential vitamins like calcium, magnesium, and potassium decrease.

Furthermore, the absence of insoluble fiber may also decrease needs for essential vitamins (e.g. magnesium) because fiber can interfere with vitamin absorption. (R)

Nevertheless, there are ways to minimize likelihood of calcium, magnesium, and potassium deficiencies on carnivore.

Calcium (?). Calcium deficiency is something that people on a carnivore diet should probably be concerned with if you’re consuming zero dairy. Various dairy products like cheese can be good sources of calcium. If you’re a non-dairy carnivore, regularly consuming bone meal (ground bones from grass-fed cows) can provide calcium.

Magnesium. A study examining 50 individuals on a paleo-keto diet found that 49 of 50 (98%) exhibited normal levels of magnesium without supplementation. (R) That said, measuring serum magnesium is far from optimal when determining magnesium status – intra-cellular magnesium would’ve been the better test. Nevertheless, magnesium supplements (e.g. magnesium glycinate) are easy to take for precaution.

Potassium. Some studies show that glucose can reduce concentrations of plasma potassium. (R) Since the carnivore diet is a zero carbohydrate diet that won’t spike glucose, potassium needs may decrease.

Sample Day of Carnivore Eating

According to the YouTuber What I’ve Learned (WIL), the mix of foods listed below should cover most recommended daily intakes (RDIs) of key nutrients.

There are compensatory mechanisms activated when various nutrients are low that are also triggered by low-carbohydrate diets – possibly decreasing requirements for a variety of nutrients in low-carb conditions.

High levels of various nutrients could be detrimental in low-carb conditions.

Will you still have bowel movements and/or poop on the carnivore diet?

Probably. Most people report no significant bowel abnormalities on the carnivore diet.

Some individuals experience an adaptation upon initiation of the carnivore diet such that gastric symptoms such as constipation, flatulence, bloating, or diarrhea occur.

However, once an individual’s gut bacteria and body become fully adapted to zero carb and zero fiber – bowel movements generally normalize.

In some cases, bowel movements significantly improve on the carnivore diet relative to one’s previous diet.

Improvements in bowel movements are commonly reported by ex-vegans who consumed excessive amounts of fiber (causing them to poop many times per day) – and individuals with gastric disorders (in which fiber was problematic).

What about purines and gout on the carnivore diet?

It’s somewhat unknown as to how you’ll react to the carnivore diet with gout – as not all people with gout are the same.

Gout is far more complex than internet diet groups and gurus care to admit – and is often influenced by various factors, including genes involved in the renal clearance of uric acid.

Suggesting that gout is caused by diet, for all individuals, is legitimately absurd.

Nonetheless, it is possible that dietary changes, including counterintuitive changes (such as going carnivore) could help some people with gout.

Several testimonials on MeatHeals.com suggest that gout may be reversible for some individuals by going carnivore.

How might the carnivore diet help cure gout in a subset of individuals?

According to the carnivore community, the chief culprit for gout flare-ups is fructose intake – not animal products.

By eliminating fructose and carbohydrates from the diet, some research indicates that uric acid concentrations and corresponding gout flare-ups may decrease – for some people. (R)

Dr. Stephen Finney and Dr. Jeff Volek state:

Uric acid levels acutely rise in the first 1-2 weeks of carbohydrate restriction due to circulating ketones competing with uric acid for kidney excretion.

In other words, blood levels of uric acid increase because the kidneys are temporarily clearing less of it while transitioning to a carbohydrate-free state.

Blood levels of uric acid need to increase for the same amount of it to be eliminated by the kidneys (because ketones are interfering).

Between 4 and 6 weeks after the initial acute spike in blood uric acid, the level drops back to or below its pre-diet level as a physiologic adaptation to ketosis.

Once fully adapted to a carbohydrate-free diet, gout flare-ups may be less severe and/or cured for certain people.

Cycling back and forth between carbohydrates and no carbohydrates can trigger gout flare ups – which should never occur on a carnivore diet.

Is the carnivore diet safe during pregnancy?

Unknown. Although many within the carnivore community claim that the carnivore diet is completely safe during pregnancy, its safety during pregnancy remains unclear – as it hasn’t been subject to scientific evaluation.

Nevertheless, many anecdotes report success with the carnivore, zero-carb diet during pregnancy and while nursing.

That said, why take a risk? It hasn’t been studied in humans. In mouse models, diets like keto can cause developmental problems.

If you’re a mother who insists on eating carnivore throughout pregnancy, I’d recommend (at the very least): (1) regular bloodwork from an experienced doctor to ensure adequate levels of nutrients and normal hormone levels and (2) being open-minded to adding in non-carnivore foods if necessary to improve your nutritional status.

Carnivore Diet Recommendations

Included below are recommendations that I have for anyone who seriously wants to follow a carnivore diet – especially over a long-term.

Adapt to the diet. It generally takes people several months to fully adapt to the carnivore diet. When initially going carnivore, many people feel worse for awhile as aspects of physiology (e.g. the gut microbiome, brain, hormones) adjust to an exclusively-carnivore diet.

Avoid raw meats. It is generally recommended to avoid consuming raw meat on the carnivore diet. However, many people are brainwashed by social media (i.e. YouTube) carnivore diet gurus claiming that raw meat is superior for health relative to cooked meat. A paper by Hinney (2018) emphasizes that raw meat intake is associated with increased risk of serious (i.e. life-threatening) infectious diseases (e.g. bacteria, parasites, etc.). (R)

Avoid processed meats. Although occasionally consuming processed meats probably won’t kill you, research suggests that highly processed meats are associated with an increased risk of cancer – whereas unprocessed meats are not. While following the carnivore diet, it is recommended to find a quality source of unprocessed meats.

Discontinue if health worsens. If at any point during a carnivore diet your health worsens and/or you experience a serious adverse reaction – do not hesitate to discontinue the diet. Don’t feel as though you must continue with the carnivore diet because other people are getting favorable results. This diet isn’t a good fit for everyone.

Ensure adequate nutrition. It’s 100% possible to become deficient in key nutrients while on the carnivore diet. Although you may not need the daily quantities of nutrients that the RDA recommends – any longstanding deficiencies in essential nutrients could cause detrimental health effects (some of which may be permanent). Eating a nose-to-tail style carnivore diet can help minimize risk of nutrient deficiencies – but you may want to supplement with things like vitamin C, magnesium, and calcium (to name a few).

Exercise regularly. As an adjunct to the carnivore diet, I highly recommend exercising regularly. In the Greenland Eskimo tribe that ate raw carnivore, health outcomes were relatively good – but these Eskimos exercised extensively (sometimes for 24 to 36 hours straight). Any type of exercise (including walking) may partially negate or protect against adverse health effects of a carnivore diet (if there are any).

Grass fed & wild caught. Although many people get good results on the carnivore diet with grain-fed beef and farmed fish, it’s probably better to get grass-fed/grass-finished beef with wild caught fish. Why? The omega-3 fatty acid content will likely be higher in the grass-fed beef and wild-caught fish.

Medical evaluations. Throughout the year, I recommend seeing a licensed medical doctor for tests to ensure that your health stays optimal on a carnivore diet. Below are just some of the tests that I recommend.

Lipids: Check your cholesterol (HDL, LDL, total cholesterol) and triglycerides to ensure that numbers are near healthy ranges.

Vitamin levels: Ensure that vitamin levels are within normal ranges such as calcium, magnesium, vitamin D3, iron, etc. If levels are significantly greater or less than normal – work with your doctor to get them back within a healthy range.

Modulate fat to protein ratio: During a carnivore diet, you may want to play around with the ratio of fat to protein that you consume. Some people achieve better health with a higher ratio of fat to protein – whereas others achieve better health and perform better with a lower ratio of fat to protein. If you aren’t feeling well on the diet, you may want to tweak the fat and protein amounts.

Objectively monitor mood, cognition, energy. While on the carnivore diet, I recommend regularly monitoring your mood, cognition, and energy. If you experience: worsening of your mood or mental health; cognitive decline; and/or severe fatigue – you may want to discontinue the diet or make some modifications until things normalize or improve.

Optimize cook temperature & duration. Cooking meat at high temperatures for a long duration (e.g. grilling) creates carcinogenic compounds like heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs). To minimize intake of these carcinogens, it is recommended to cook meat at lower temperatures for limited durations.

Track macronutrients & micronutrients. Although many individuals do the carnivore diet and feel better without tracking macronutrients and micronutrients – it may be beneficial to track macros and micros. Tracking macronutrients on the carnivore diet (protein and fat) can make it easier to accomplish goals such as: gaining fat, losing fat, building muscle, entering ketosis, etc. Tracking micronutrients will help you understand whether your intake of various nutrients (vitamins, minerals, etc.) are adequate for optimal health on the carnivore diet.

Carnivore diet “pros” (Advantages)

Potential benefits or “pros” associated with the carnivore diet are listed below.

grass-fed cows

Amino acids. The carnivore diet includes animal products that contain all 20 essential amino acids. Consistently consuming animal products can elevate amino acid concentrations, which for some people, may be beneficial – particularly for mental health and brain function.

Bioavailable nutrients. The carnivore diet provides nutrients in an extremely bioavailable format – making them easy for the body to absorb. Additionally, many of these nutrients are absorbed and utilized more efficiently in the absence of fiber and carbohydrates.

Effortless weight loss. The carnivore diet should make it easy for most people to lose weight – particularly body fat – due to its high protein content plus fat. High protein diets can increase satiety (especially in conjunction with fat), reduce food cravings, modulate hormone levels, and increase metabolic rate (slightly more than other macros) due to its thermic effect. Protein also preserves muscle, yet is difficult for the body to store as fat.

Killing fewer total animals (?): Consuming nothing but 100% grass-fed, local beef might result in fewer animal deaths per year than consuming other diets (omnivorous, vegan, etc.) – in which many animals die from field clearing and plowing practices. Why? Because one or two cows will provide hundreds of pounds of meat, which can fuel one person for the entire year.

Less pesticide use: Fruits and vegetables require a lot of pesticides to ensure favorable appearance, ripeness, and consumer satisfaction. Unfortunately, the chronic use of these pesticides may: poison animals and humans, negatively impact soil quality, pollute groundwater, and damage ecosystems. Moreover, pesticides can be costly for farmers. Raising grass-fed cows does not require pesticides.

Soil quality enhancement: Research suggests that the free-range grazing of farm animals like beef cattle, sheep, and horses improves soil quality for farmers. Monocrop operations in which no animals graze are associated with poorer soil quality – and increased rates of soil-borne disease.

Note: The above arguments may only apply to persons who are consuming 100% local, grass-fed beef.

Medical conditions. Many anecdotes suggest that the carnivore diet might help with various medical conditions such as: autoimmune disorders; gastric disorders; and psychiatric disorders. Attenuation of symptoms and/or flare-ups are commonly reported by persons in the carnivore community.

Autoimmune disorders

Gastric disorders

Psychiatric disorders

Simplistic. The carnivore diet is relatively minimalistic and simple for most people to follow. In fact, it’s so simple that some people just eat one animal – cows. Consuming things like grass-fed beef, organ meats (liver, brain, heart, etc.), and natural fats can help meet most nutritional demands. Some people claim that the carnivore diet actually saves them money relative to a prior diet with processed foods and/or a variety of foods.

Carnivore diet “cons” (Drawbacks)

Potential drawbacks or “cons” associated with the carnivore diet are listed below.

Adaptation phase. For some individuals, it can take awhile to fully adapt to the carnivore diet.

N-Nitroso compounds: N-Nitroso compounds in cured and processed meats have been linked to cancer.

Pesticides & toxins: Grain-fed cows and/or other animals from factory farms might be full of pesticides (from consuming sprayed crops) and other toxins (such as exogenous hormones to maximize growth or infectious diseases from living conditions).

Polycyclic aromatic hydrocarbons: These compounds form when meat is cooked at high temperatures – and may cause cancer, especially when ingested regularly in large quantities.

TMAO: TMAO is a compound that’s formed when gut bacteria metabolize choline, betaine, and carnitine from meat and other animal products. Studies show that elevated TMAO may increase risk of cancer.

Cost. For some individuals, following a carnivore diet is expensive – particularly if all the meat is grass-fed. Most people pay between $6 and $10 per pound of grass-fed beef.

If you’re consuming 3 lbs. of grass-fed beef per day on carnivore, that will cost between $18 and $30; not something everyone can afford.

If you factor in the costs for all other animal products that you consume, plus any dietary supplements that you end up taking (e.g. glycine, bonemeal, etc.) – the cost will further increase.

Environmental impact. Research suggests that high dietary intake of animal products elicits a multitude of deleterious environmental effects.

According to Meyer and Reguant-Closa (2017), meat production degrades the environment more than all other methods of industrial food production. (R)

Beef, lamb, pork, turkey, fish, and cheese are among the highest emitters of greenhouse gases at approximately 4 kg CO2 eq/kg edible weight.

Also, factory-farmed livestock require a significant amount of grains (e.g. corn, wheat, soy) for feed – which further adds to the cumulative greenhouse gas burden associated with their production.

In other words, the corn, wheat, and soy used specifically for animal feed emits some initial greenhouse gases – and then the livestock emits significantly more (in addition to the initial gases from the crops used in the animal feed).

Research by UNESCO-IHE Institute for Water Education indicates that beef uses up 20 times more water per calorie than grains or potatoes.

Per gram of protein, milk, eggs, and chicken have a water footprint that’s around 1.5 times larger than that of legumes – and beef has a water footprint that’s around 6 times larger than legumes. (R)

It’s also necessary to underscore that meats (e.g. beef) are routinely transported internationally (e.g. from Australia and Brazil to U.S.) – and livestock are routinely transported across the country.

The fuel emissions required for this transportation should be factored into the cumulative detrimental effect of meat consumption on the environment.

In terms of the environment, livestock production is associated with substantially greater: (1) greenhouse gas emissions – and global warming; (2) biodiversity loses; and (3) freshwater depletion – relative to the production of fruits, vegetables, and whole grains (in quantities that match edible calories and protein levels of meats).

Knowing this, following the carnivore diet may be more damaging to the environment than diets with lower intakes of animal products.

Additionally, though many carnivore dieters only consume local pasture-raised meat – some might consume factory farmed meats due to their lower cost and/or convenience.

It is estimated that at least 2 in 3 livestock worldwide are raised in factory farms (70 billion per year).

Large-scale industrial operations in which thousands of animals (chickens, turkeys, cows, pigs) are raised to be slaughtered for food.

Factory-farmed animals are often confined in small spaces (negatively affecting wellbeing) and produce too much waste for the surrounding land to handle, ultimately polluting the land and nearby waterways.

Additionally, animals in factory farms are slaughtered well before their natural life expectancies.

For example, cows, sheep, and pigs have natural life expectancies of ~20 years, and factory farming shortens these expectancies to ~3 to 5 years (cows and sheep) and ~7 months to 3 years (pigs).

Persons consuming factory farmed meat on a carnivore diet are supporting an industry in which profit is the primary motive; animal welfare and environmental impact are typically afterthoughts. (R)

And while consuming pasture-raised (non-factory farmed) cows from local farmers is routinely recommended to maximize animal welfare, pasture-raised cows: (1) produce more methane; (2) contribute to nitrate contamination of surface and groundwater in some areas of the world; (3) may require more nutrient inputs to reach the same production endpoints (due to inefficiencies).

It is also suggested that welfare-friendly pasture-raised animals might be at greater risk of infection from Salmonella.

Lastly, research by Siegford et al. (2008) states that welfare-friendly farming requires more land area per animal (or per unit of product) – meaning it may actually be less environmentally sustainable than factory farming. (R)

Feelings can be misleading. Many people claim to subjectively “feel better” on a carnivore diet, but feelings can often be misleading.

For some individuals, the “feeling better” on a carnivore diet may not correlate with favorable changes in biomarkers or health.

Additionally, it’s reasonable to surmise that a subset of persons who “feel better” on the carnivore diet might objectively experience worsening of various health markers.

Furthermore, some people might “feel better” for a while when doing any new diet as a result of: (1) eliminating problematic foods and (2) a placebo-like response (wherein a person’s physiology shifts in a way that improves wellbeing or mood – as a result of a strong belief that the diet will help).

Just because you feel better on the carnivore diet does not necessarily mean it’s ideal for your body.

Long-term safety unknown. The long-term safety of a carnivore diet in humans is relatively unknown. No high-quality studies have examined the long-term impact of a strict carnivore diet on human healthspan and lifespan.

At this time, nearly all data from nutritional epidemiology indicate that longer healthspan and lifespan are associated with greater intakes of: (1) fiber; (2) fruits and vegetables; (3) whole grains; and (4) monounsaturated and polyunsaturated fats.

Though data from nutritional epidemiology can be subject to healthy user biases, it shouldn’t be completely dismissed.

It’s fair to suggest that dietary choices associated with increased healthspan and longevity could be causally implicated in the increased healthspan and longevity. (R)

Since there are: (1) zero data indicating that a carnivore diet will improve healthspan and/or lifespan, and (2) some data indicating that red meat, excess saturated fat, and excessive animal protein correlate with reduced lifespan – following a carnivore diet could be perceived as risky, particularly over a long-term.

Medical conditions. Despite the fact that many individuals with medical conditions derive benefit from the carnivore diet – other people might experience an exacerbation of preexisting medical conditions and/or onset of new medical conditions as a result of carnivore. (R)

Autoimmune disorders. Many people report worsening of autoimmune symptoms with consumption of animal protein. In fact, many people with autoimmune disorders do better on vegan and vegetarian diets – than diets with meat.

Diabetes. Some individuals with diabetes may experience poorer blood-glucose regulation and/or high blood sugar while on the carnivore diet.

Gastric disorders. Many individuals with gastric disorders experience fewer symptoms with normal or above-average intakes of fiber than the general population.

Meat allergy. Some people are allergic to red meat (beef and pork) as a result of being bitten by the Lone Star tick. If you have this allergy, obviously the carnivore diet shouldn’t be attempted (as the allergy can be life-threatening).

Psychiatric disorders. Individuals with anxiety, depression, bipolar disorder, and/or schizophrenia may experience a worsening of symptoms on a carnivore diet. For example, research shows that excessive cholesterol and IGF-1 are associated with worsening of depression.

Uric acid disorders. Many animal foods on the carnivore diet contain high concentrations of organic compounds called “purines” which are broken down into uric acid within the body. For some individuals, consuming high purine foods can cause uric acid to accumulate and damage the body.

Not evolutionarily consistent. From an evolutionary perspective, humans are opportunistic omnivores and function effectively on a varied, omnivorous diet.

Although some evidence suggests that meat consumption may have fueled evolutionary advances in brain development – other evidence suggests that advances in brain development were attributable to carbohydrates. (R1, R2)

Furthermore, the reality is that humans (H. Sapiens) evolved to be omnivorous. Although evolving to be omnivorous doesn’t necessarily mean that an omnivorous diet is “optimal” for human health and/or performance – it does suggest that humans functioned well on a varied diet.

According to Challa and Uppaluri (2019), early Paleolithic humans consumed a variety of foods, including plants (e.g. tubers, seeds, nuts, wild grown barley); insects; seafood; and animals (~3% of the total diet). (R)

The researchers concluded that early humans consumed a variety of high-quality foods that were rich in nutrients and fiber.

Because the carnivore diet lacks carbohydrates and fiber, it may be an evolutionary mismatch and downright suboptimal for modern humans.

If the carnivore diet is an evolutionary mismatch for modern humans (which research suggests), it might yield deleterious health effects if followed long-term.

Questionable during pregnancy & early childhood. At this time, zero studies have directly examined the effects of a carnivore diet in fetal development (while pregnant), while nursing, and throughout early childhood.

Pregnant and nursing mothers should be cautioned against following a carnivore diet unless endorsed by a dietician and/or licensed medical professional.

Though it might be possible to have a healthy pregnancy and baby on a carnivore diet – it might also be possible that the carnivore diet interferes with brain development and/or organ growth (relative to consuming a nutrient-dense, varied diet with complex carbohydrates).

Why risk potential developmental abnormalities and/or permanent deficits for an unborn baby because you wanted to stick with the carnivore diet? This goes against all professional nutrition and medical recommendations.

A subset of carnivore dieters report that the restriction interferes with social life and relationships – and can cause depression.

Why? Following a carnivore might make it difficult for some people to enjoy themselves at social gatherings with food – because: (1) many foods may not be carnivore-compliant; (2) other people might encourage them to stop the carnivore diet and/or criticize the diet; and/or (3) it may be difficult to resist temptation of carbohydrate-based foods at these gatherings.

Another thing to consider is that restricting yourself to the carnivore diet for a long-term might be extremely difficult due to the fact that you might crave or miss a variety of foods such as: fruits, vegetables, and whole grains.

Should you reintroduce these foods (at a future date) after you’ve been carnivore for a while, you might find yourself binge eating – due to the fact that you deprived yourself of a macronutrient for such a long duration.

Some people function better with extra vitamins. Numerous carnivore dieters claim to have zero vitamin deficiencies, however, many of those who claim to have zero vitamin deficiencies have never been properly evaluated by a medical professional for vitamin deficiencies.

Furthermore, in the subset of carnivore dieters who have been tested for vitamin deficiencies, the tests chosen are often suboptimal. For example, serum magnesium and calcium tests are significantly less accurate than intracellular tests.

Nonetheless, even if the carnivore diet provides adequate levels of vitamins, it’s known that some individuals function better with vitamin surpluses – or intakes of vitamins that exceed the recommended daily allowances (RDAs).

For example, some people function better with extra magnesium, calcium, vitamin C, manganese, folate, and glycine – relative to what can be naturally attained on a carnivore diet.

In the persons who function better with above-average intakes of various vitamins, following a carnivore diet may be suboptimal (especially without supplementation).

Though nutritional epidemiology cannot establish cause and effect (e.g. eat this food or food group for health), it is able to reveal foods that are consumed more frequently by healthy and long-lived individuals.

Everything considered, nutritional epidemiology reveals that, at the very least, high intakes of: fiber, nuts/seeds, vegetables, fruits, and whole grains – do not appear to compromise health or longevity.

Presently, the only support for the idea that a carnivore diet improves health is derived from a series of medically-unverified anecdotes on the internet.

Not only is scientific support for a carnivore diet lacking, the carnivore diet (only animal products) contradicts the strongest nutritional epidemiologic data.

Carnivore Diet Criticisms & Counterpoints

Ages the brain. Many claim that the carnivore diet ages the brain due to its high intake of animal protein, cholesterol, and saturated fat.

Many people report cognitive enhancement and mood stabilization on the carnivore diet (relative to a previous diet).

Bad for the gut. Another common claim is that the carnivore diet is horrible for “gut health” and the gut microbiome. Some individuals suggest that gram-negative bacteria in the gut yield metabolites from animal products like TMAO which may cause cancer.

Moreover, the carnivore diet may just change the gut (neither for “better” or “worse”) as an adaptive response to only consuming animal products. (R)

Lastly, though gut microbiome abnormalities are discussed frequently in mainstream media as being linked to medical conditions – causality is lacking (gut microbiome abnormalities are probably a response to medical conditions – rather than the cause).

Blood sugar problems. Some claim that the carnivore diet will cause high blood sugar, prediabetes, or type 2 diabetes. Furthermore, various anecdotes have reported unhealthy elevations in fasting blood glucose while on the carnivore diet.

Additionally, some individuals will experience a reversal of prediabetes or type 2 diabetes – with concurrent increased insulin sensitivity while on the carnivore diet (probably due to body fat loss).

Cancer risk. Critics of the carnivore diet claim that the diet might increase cancer risk to a significant extent – especially if followed over a long-term.

The combination of elevated: TMAO (formed in the metabolism of animal products); HCAs and PAHs (from grilling or cooking meat at high temps); choline (R); methionine; IGF-1; heme iron; and amino acids might fuel cancer growth, particularly in the context of a low-antioxidant diet like carnivore.

Counterpoint: Just because things are linked to cancer does not mean that they cause cancer. Furthermore, carnivore dieters can do things to reduce cancer risk like: limiting calories, cooking meat at lower temperatures, avoiding processed meats, and avoiding excessive protein.

Lastly, the carnivore diet might elicit a natural antioxidant response within the body (e.g. upregulation of glutathione) to decrease cancer risk in a similar manner to consumption of exogenous antioxidants.

Cardiovascular risks. Critics of the carnivore diet suggest that consuming nothing but animal products (many of which are high in saturated fat and cholesterol) will increase risk of cardiovascular diseases like: atherosclerosis, coronary heart disease, congestive heart failure, and stroke – especially in genetically-susceptible individuals.

Counterpoint: Many anecdotes from within the carnivore community highlight significant improvements in cardiovascular biomarkers while on the carnivore diet (relative to previous diets).

High blood cholesterol and triglycerides can interfere with blood flow and harden the arteries in ways that increase risk of cardiovascular complications like heart attack, stroke, and peripheral artery disease.

Counterpoint: Assuming a person on the carnivore diet doesn’t carry genes associated with increased risk of hypercholesterolemia (e.g. LDLR and PCSK9 mutations) and/or hypertriglyceridemia, lipid changes on the carnivore diet may not be a big deal.

Counterpoint: The carnivore diet eliminates things like sugar and refined carbohydrates – both of which can induce cognitive impairment. (R)

Furthermore, many carnivore dieters find it difficult to overeat and are: (1) reducing calories (relative to their previous diets) and (2) losing body fat. Both caloric reduction and fat loss are associated with improvements in cognition.

Cult-like following. Critics of the carnivore diet suggest that the diet is “cult-like” wherein carnivore dieters frequently: (1) assume their diet is superior to other diets; (2) criticize all other diets; (3) ignore, dismiss, or criticize all legitimate criticisms of the carnivore diet; and (4) criticize persons who found the carnivore diet unhelpful (commonly suggesting that they “did it wrong.”).

Moreover, many carnivore dieters think they’re somehow blessed with super genius diet knowledge (relative to others) and end up entrenched in fringe online echo chamber type groups (wherein carnivore is always marketed as good – and other choices are marketed as bad).

Counterpoint: Though the carnivore diet has acquired a cult-like following online (which includes many fanatical adherents), many extreme diets have cult-like followings including: vegan, vegetarian, keto, paleo, fruitarian, lectin-avoidance, etc.

Just because a diet has a cult-like following does not necessarily mean the diet is unhealthy or shouldn’t be followed.

Many people who find the carnivore diet helpful are merely trying to exchange research and anecdotes with likeminded individuals.

Since the carnivore diet is extreme, it’s difficult to meet people in-real-life (IRL) that are also carnivores – hence the need for these carnivore diet groups.

Moreover, there are many sensible carnivore dieters like Mark Bell (powerlifter) who listen to critics of the carnivore diet and acknowledge that: (1) the carnivore diet may have some drawbacks; and (2) non-carnivore diets can also be healthy.

Counterpoint: Though many speculate that zero fiber diets cause digestive problems and gastric disorders, there’s no strong research proving causality.

What’s more, several studies and a plethora of anecdotes suggest that low fiber and zero fiber diets may actually improve digestion and reduce the severity of preexisting gastric disorders – for a subset of persons.

While it’s certainly plausible that one might experience various gastric abnormalities immediately after transitioning to the carnivore diet (based on the fact that the gut microbiome needs time to adapt to a zero carbohydrate, zero fiber diet) – these abnormalities are generally manageable and short-lived.

Some might even suggest that, once adapted to carnivore, digestion of food becomes more efficient due to the fact that the body receives similar foods (e.g. beef) on a regular basis.

Some have argued that ongoing animal agriculture is environmentally unsustainable – especially with modern increases in demand.

Counterpoint: Although animal agriculture may contribute more significantly to biodiversity loss, climate change, and freshwater depletion – relative to non-animal agriculture – there are far bigger contributors to the global ecological footprint.

To put things in perspective, a report from the IPCC (International Panel on Climate Change) indicates that electricity and heat production contributes 25% to greenhouse gas emissions – the most out of any sector. (R)

Data from the IPCC suggest that AFOLU (agriculture, forestry, and other land use) contribute 24% to greenhouse gas emissions. (R)

However, agriculture accounts for 10-12% of this figure – and animal agriculture accounts for a smaller subset (~2-4%). (R)

It’s also necessary to underscore the fact that greenhouse gas emissions from animal agriculture can be reduced by altering: livestock feeding practices; breeding and management practices; and manure management.

It’s also necessary to underscore the fact that pasture-raised animal agriculture may improve soil quality (via grazing and manure) and aspects of biodiversity in ways that non-animal agriculture is incapable of doing.

Ethically questionable. Critics of the carnivore diet argue that the diet is unethical on the basis of: (1) animal suffering and deaths and (2) environmental impact. (R1, R2)

Animals in factory-farms are confined in small places, fed unnatural food, injected with antibiotics/hormones, and slaughtered long before their natural life expectancies.

Slaughtering methods can vary among countries – with some countries engaging in more ethical slaughter practices than others. Nevertheless, many animals worldwide are likely slaughtered inhumanely.

Furthermore, the waste from factory farms is a significant polluter of nearby land and waterways. Animal agriculture (regardless of whether factory-farmed) also emits more greenhouse gases than non-animal agriculture.

Because a carnivore diet will (1) increase animal suffering and deaths and (2) damage the environment to a greater extent than diets with fewer animal products – some ethicists argue that reducing or abstaining from animal consumption is a moral imperative.

Counterpoint: Not all carnivore dieters consume factory-farmed meat. A subset of carnivore dieters only purchase local animal products that are ethically raised (e.g. grass-fed, pasture-raised cows without antibiotic and hormone injections) and humanely slaughtered.

Though the argument (put forth by carnivore dieters) that more total animals die from plant-related agriculture (e.g. small rodents like field mice from harvesting tools and pesticide poisoning) is somewhat misleading (especially if made by persons who consume grain-fed beef), it may have some validity if presented by someone who only consumes local grass-fed beef (and zero other animals).

The Animalist (an animal advocate and vegan) was quoted on Medium stating:

“If meat eaters stopped eating grains and strictly only ate Australian grazing cattle instead, then, in a way they would have a point.” (R)

Consumption of local grass-fed beef might reduce total animal deaths and suffering relative to omnivorous diets – and possibly even vegan diets.

However, this assumes that one ONLY eats grass-fed beef on the carnivore diet – and possibly eggs from free-range hens and/or oysters (non-sentient) – but no other animal products.

Although some vegans might argue that smaller animals killed in the harvesting of non-animal agriculture (e.g. grains) are less sentient than larger animals like cows – this is debatable – as animal size cannot be used to predict sentience.

Furthermore, it should be stated that the carnivore diet often helps people with weight loss by promoting satiety (which commonly yields a significant reduction in total daily energy intake relative to a previous diet).

If one’s total daily energy intake significantly decrease on the carnivore diet (relative to a previous diet), this could have a beneficial impact on the environment [in select cases] because fewer resources might be needed to reach satiety.

For example, if you consume a variety of processed carbohydrate foods for a total of 6000 calories per day (because you never feel full), the ecological footprint might outweigh consuming just 1500 calories per day of grass-fed beef on a carnivore diet.

Nonetheless, if a person consumes local, pasture-raised, grass-fed beef – and consumes fewer calories than his/her previous diet – this might: (1) decrease total animal deaths (no harvesters or pesticides are needed for the beef) and (2) reduce deleterious transportation-related greenhouse gas emissions (fruits, vegetables, and crops are often shipped from other states or countries).

It should also be emphasized that strides have been made towards improving animal welfare in the United States by: (1) redesigning livestock housing; (2) redesigning slaughter facilities; (3) improving slaughter practices; (4) improving conditions of livestock transport; and (5) modifying animal handling (in ways that decrease stress).

It’s also possible that with genetic engineering, scientists will be able to edit the genomes of livestock such as to inhibit or reduce sentience – and/or prevent them from feeling any type of pain (physical and/or psychological).

In time, conventional animal agriculture may be phased out in favor of cultured (lab-grown) meat which will result in zero animal suffering or deaths – and could be better for the environment than all forms of agriculture.

Additionally, if the carnivore diet is the only diet that dramatically improves the health, wellbeing, and/or satisfaction of a highly-sentient human (such as by reversing a serious medical condition like major depressive disorder) – most would agree that the diet should be pursued.

Furthermore, it’s reasonable to hypothesize that carnivore dieters might be less likely than average to generate “food waste” than other diets – which should improve the environment.

Research by Conrad et al. (2018) shows that fruits and vegetables are associated with the greatest food waste per capita. (R)

Worldwide, foods with the highest wastage rates include: fruits and vegetables (accounting for 45%); roots and tubers (45%); and cereals (30%). This means that nearly half of all fruits, vegetables, roots, tubers and cereals produced are wasted. (R)

Lastly, one could argue that many things on Earth are unethical including: having kids (we have plenty of people on Earth); buying and using a phone (many are manufactured in hazardous conditions by underpaid workers); using mainstream transportation like cars, airplanes, etc. (all of which emit greenhouse gases); et al. – however, just knowing these facts will not stop people from doing what they want.

Expensive. Critics of the carnivore diet argue that the diet is expensive relative to omnivorous and vegan diets.

Counterpoint: Any diet can be expensive. Many people spend lots of money on omnivorous, keto, and vegan diets – particularly people who only buy “organic” from places like Whole Foods.

Think about all of the gourmet food items people buy while on standard omnivorous diets – and while following fad diets (e.g. buying vegan or keto snack bars).

If you’re unable to afford a carnivore diet, a simple solution is to not follow it.

Additionally, it should be noted that many people are able to find low priced animal products when they: (1) purchase directly from local farmers AND (2) buy in bulk (e.g. an entire cow).

Lastly, various items included within a carnivore diet such as eggs and organ meats are extremely cheap (and sometimes given away for free).

When considering that carnivore dieters probably: (1) aren’t wasting money on overpriced gourmet snack foods; (2) consuming fewer total calories on a carnivore diet (relative to a previous diet); and (3) buying in bulk – the total price-tag for carnivore may be cheaper than expected.

Feelings can be misleading. Vegan critics of the carnivore diet such as Dr. Joel Fuhrman have argued that people feeling better on the carnivore diet does not necessarily indicate that the diet is healthy. He suggests that “feelings can be misleading” in that many people feel better after smoking cigarettes and using illicit drugs – but the activity is detrimental to health.

Counterpoint: Feeling better after smoking cigarettes and using illicit drugs is most often transient – such that drug use provides a short-term buzz, followed by a crash.

Many people end up feeling significantly worse after smoking cigarettes and using illicit drugs over a long-term due to deterioration of health.

Additionally, one could argue that nicotine is the specific component within cigarettes that makes people feel better – and that nicotine may actually have some long-term health benefits.

Furthermore, it’s important to acknowledge that feelings are sometimes accurate indicators of whether a diet is improving health.

People tend to feel better when they eat healthy versus when they eat junk (i.e. hyperpalatable, non-nutritious) foods.

Many people on the carnivore diet are reporting that they feel significantly better over a long-term – and that “feeling better” correlates with improvements in biomarkers (e.g. lower CRP, stable blood glucose, optimal hormone levels etc.).

If someone loses weight in the form of body fat on the carnivore diet from a previously overweight state, research suggests that this can improve mood.

Elimination of certain foods and/or compounds from one’s diet via transitioning to carnivore could also help decrease inflammation and improve subjective feelings – and objective biomarkers.

Moreover, the bioavailable amino acids and nutrients provided on a carnivore diet might correct preexisting deficiencies which were associated with anxiety, depression, and fatigue.

Lastly, let’s hypothetically assume that someone subjectively “feels better” but is actually in worse health because of the diet.

Let’s also assume that the carnivore diet will cut a person’s life expectancy short by 5 to 10 years (relative to their previous diet).

My guess is that most people would rather “feel better” for the majority of their life on a carnivore diet and live to ~70 than feel miserable on a previous diet and live to ~80.

Sometimes feelings should actually trump objective biomarkers – especially if the person was miserable and crippled with severe fatigue and/or depression on a previous diet.

Gout flare-ups. Critics of the carnivore diet argue that it will cause significant gout flare-ups in susceptible individuals. Why? Because many animal products (meat and seafood) are high in purines which are broken down into uric acid within the body.

As a result, some people with gout will experience elevations in uric acid levels (hyperuricemia) and gout flare-ups. Anyone with a history of elevated uric acid should proceed with extreme caution if attempting to follow the carnivore diet. (R)

Counterpoint: It is true that a subset of persons with hyperuricemia and gout will be unable to tolerate the carnivore diet (largely due to genetics).

However, select number of individuals with gout may have no issues tolerating the carnivore diet.

Hormone imbalances. Critics of the carnivore diet state that the diet could cause serious hormone imbalances due to the fact that it: (1) eliminates carbohydrates; (2) is high in saturated fat; (3) may provide excessive animal protein; and (4) may provide inadequate concentrations of essential nutrients.

Moreover, it’s necessary to underscore the fact that some people will have hormone abnormalities regardless of their diet (due to genetics, body composition, medical conditions, and/or medication use).

For this reason, we cannot conclude that the carnivore diet universally disrupts hormones.

Humans are omnivores. Critics suggest that it is unhealthy to follow a carnivore diet because humans are omnivores (i.e. entities that eat both plants and animals for food).

Counterpoint: It is true that humans are omnivores, however, the fact that humans are omnivores shouldn’t be automatically extrapolated to suggest that a carnivore diet is unhealthy.

Just because the human species is overwhelmingly omnivorous does not mean that consuming a well-planned yet atypical diet (e.g. carnivore, vegan, etc.) is detrimental to health.

As evidenced by numerous anecdotes, many people are in good health, high-functioning, and/or thriving on the carnivore diet.

Lack of antioxidants. Critics of the carnivore diet (e.g. Dr. Joel Fuhrman) argue that the carnivore diet is unhealthy and will accelerate biological aging and/or induce diseased states because it lacks antioxidants.

Counterpoint: At this time, it remains completely unclear as to whether dietary antioxidants really improve human health.

A paper by Huang (2018) states that it’s unknown whether there are legitimate benefits from dietary antioxidant consumption on oxidative stress status, disease prevention, and overall health. (R)

An earlier paper by Gordon (2012) states that dietary antioxidants aren’t efficiently absorbed and are commonly metabolized into derivatives that decrease antioxidant capacity. (R)

In other words, plant antioxidants exhibit poor bioavailability, are minimally absorbed, and are typically eliminated from the body before reaching cells.

Proponents of the carnivore diet argue that dietary antioxidants are completely unnecessary due to the fact that the body upregulates its own endogenous antioxidant responses (e.g. glutathione production) when necessary.

Some carnivore dieters also suggest that consumption of exogenous antioxidants from plants might be harmful to humans.

However, for other individuals, the carnivore diet either: (1) has no effect on inflammation OR (2) markedly decreases systemic inflammation.

When considering the fact that the carnivore diet: (1) eliminates foods, compounds (e.g. gluten, lectins, oxalates, etc.), and/or toxins associated with sensitivities and allergies; AND (2) commonly leads to fat loss (via caloric reduction) – it makes logical sense that this diet has potential to dramatically decrease inflammation in a subset of individuals.

Nutritionally inadequate. Many critics believe the carnivore diet is nutritionally inadequate such that it might yield severe nutritional deficiencies if followed over the long-term. Long-term nutritional deficiencies on a carnivore diet could cause permanent physiologic damage, increase risk of disease, shorten healthspan, and shorten lifespan.

Counterpoint: Any poorly planned diet has potential to cause a nutritional deficiency.

Furthermore, because the RDAs (recommended daily allowances) of most nutrients are generalized (rather than individualized), it’s unlikely that preexisting RDAs are optimal for every individual.

In fact, it’s reasonable to speculate that various individuals might function better with intakes below the RDAs for certain nutrients.

Nutritional needs can vary among humans (based on genes); what’s optimal for one person could be suboptimal for another.

A well-planned nose-to-tail carnivore diet can be nutritionally complete – covering the recommended daily allowances of all vitamins and minerals.

Evidence suggests that: (1) the body likely absorbs many nutrients more efficiently from animal products than non-animal foods; AND (2) the body absorbs many nutrients more efficiently in the absence of carbohydrates and fiber.

So on the carnivore diet, reduced intakes of various nutrients (relative to other diets) may still fulfill the nutritional requirements for healthy functioning.

Moreover, cautious carnivore dieters can get regular lab tests to evaluate levels of important vitamins within the body.

If nutrient deficiencies are detected, supplements can be administered to normalize nutritional status.

Lastly, it should be known that overnutrition (i.e. oversupply of nutrients) can cause health problems – and following a carnivore diet can decrease likelihood of overnutrition.

In some cases, it’s possible that nutritional status improves on a carnivore diet because a person transitions from a state of overnutrition (consuming excess nutrients) to one of adequate nutrition (without excess).

Poor exercise performance. Critics have stated that the carnivore diet will likely interfere with athletic and exercise performance – particularly in elite athletes.

This criticism is supported by multiple studies in which low-carbohydrate diets impaired exercise performance.

Experts like Kanter (2018) state that current research still points to carbohydrate as an indispensable energy source for high-intensity performance.

Kanter further notes that carbohydrates are the only macronutrient that can be broken down rapidly enough to provide energy during periods of high-intensity exercise. (R)

Furthermore, it seems as though elevated blood levels of non-esterified fatty acids and ammonia during exercise (on low-carbohydrate, high-fat diets) can induce fatigue.

Most elite athletes regularly consume carbohydrates to maintain peak performance – and probably wouldn’t do well on a carnivore diet.

Additionally, some carnivore dieters have commented that (subjectively) it seems as though their exercise performance declines on a carnivore diet (versus a diet with carbohydrates).

Counterpoint: According to research by Chang et al. (2017), there’s some evidence that low-carbohydrate, high-fat diets might enhance aspects of exercise performance.

Chang et al. suggest that low-carbohydrate, high fat diets may initially impair exercise performance, however, once an individual has been on the diet for 3+ months (and fully adapted) – it may enhance endurance performance.

Additionally, it should be emphasized that there’s often an adaptation phase to the carnivore diet wherein athletic performance initially declines, but then normalizes (similar to pre-carnivore) after 3+ months.

Paul Saladino has suggested (in an Elliott Hulse interview) that select carnivore dieters may benefit from addition of 1 or 2 tolerable carbohydrate sources (e.g. white rice) before an athletic event or workout if performance has declined on carnivore and/or noticeably improves with carbs.

Potentially unsafe. Critics of the carnivore diet suggest that it is potentially unsafe, especially if followed for a long-term.

Why? Because the best available evidence from nutritional epidemiology indicates that diets: high in red meat; high in saturated fat; low in fiber; low in fruits; and low in vegetables – are associated with poor health and early mortality.

Conversely, the best nutritional epidemiologic data indicate that diets: lower in red meat; lower in saturated fat; higher in fiber; higher in fruits; higher in vegetables; and higher in whole grains; – are associated with better health outcomes and longevity.

Also, the carnivore diet can significantly increase IGF-1, methionine, heme iron, TMAO, and amino acids – which some suspect could increase risk of cancer and other diseases – especially if consumed in excess.

If the carnivore diet is poorly planned/executed over a long-term such that extreme nutrient deficiencies occur – this could cause permanent neurological damage.

Counterpoint: Although epidemiologic data suggest that diets high in red meat and saturated fat are associated with poorer health outcomes and early mortality – this does not mean that the red meat and saturated fat intakes caused poor health outcomes and/or early deaths.

Why? Because many people who consume diets high in red meat and saturated fat are more likely than average to: be sedentary (instead of exercising); drink alcohol in excess; and smoke cigarettes – all of which can adversely impact health (particularly when combined).

Since many confounds may contribute to poor health outcomes among individuals with high intakes of red meat and saturated fat (and low intakes of fiber, whole grains, etc.) – from epidemiologic studies – we cannot assign sole culpability to dietary choices.

Furthermore, a brief epidemiologic study of 142 adult Greenland Eskimos on a carnivore diet (meat-only) reported that the population was mentally alert and healthy – with no significant adverse health effects resulting from dietary choices.

For this reason, we must consider the possibility that a well-planned carnivore diet could be safe for some individuals over a long-term.

Why? Because it: eliminates various compounds/foods to which people have sensitivities; eliminates sugar; reduces likelihood of overnutrition; and commonly yields calorie reduction/fat loss.

Pairing the carnivore diet with regular exercise, stress management, enjoyable socialization, and avoidance of alcohol and cigarettes – might further improve health outcomes for followers of this diet.

Although a poorly planned/executed carnivore diet is probably unsafe – the same can be said for all diets that are poorly planned/executed.

Because the carnivore diet hasn’t been extensively researched in modern, well-designed studies, it’s difficult to gauge its safety (or lack thereof) relative to other diets.

Too restrictive. Critics of the carnivore diet have stated that the diet is too restrictive to satisfy most people over the long-term.

It has been suggested (and reported by select ex-carnivore dieters) that the restrictive nature of the carnivore diet interferes with psychological wellbeing – particularly in social settings where people consume and share a variety of foods (with friends and family).

Additionally, it is thought that highly-restrictive or extreme diets (like carnivore) may provoke binge eating disorder wherein someone eventually discontinues carnivore and develops a habit of binge eating foods that were previously.

Counterpoint: Although some people feel psychologically deprived and depressed on restrictive diets (e.g. carnivore, keto, vegan) due to “missing out” on enjoyable foods, others may fair far better (in terms of health outcomes) on restrictive diets.

In the aforementioned example, this individual may consume thousands of calories more than his/her maintenance needs (i.e. calories needed to replenish lost energy – without excess) before finally achieving satiety (i.e. “feeling full”).

When the individual gets hungry again, he/she may end up craving the same foods that led to overconsumption of calories – overeating and binge eating episodes continue indefinitely – resulting in obesity (and obesity-related health complications like type 2 diabetes).

For some people, the only way to break this cycle of craving unhealthy/unsatiating foods followed by overconsumption of calories – is to go on a restrictive diet.

Not everyone fairs well on diets with “a lot of variety” (especially if the variety includes foods with high sugar, high salt, high fat – with minimal protein and no fiber).

In fact, some research suggests that monotonous diets (with fewer total food choices) are more effective in suppressing appetite, reducing food cravings, and inducing weight loss – than diets with variety. (R)

Moreover, most social gatherings and events will have carnivore options available (e.g. meats) – and the carnivore diet might have more variety than one might initially suspect (particularly in carnivore diet variations that permit consumption of dairy).

It should also be noted that many people report improved psychological wellbeing on a “restrictive” carnivore diet due to a combination of: (1) craving dissipation (due to elimination of hyperpalatable foods and stable blood sugar); (2) less preoccupation thinking about food (due to longer periods of satiety); (3) building self-discipline (adhering to a carnivore diet can be a fulfilling challenge); and (4) fat loss (this is associated with mood improvement).

Unfeasible for everyone. Critics argue that the carnivore diet is impractical and unfeasible for most people in the world to follow – so therefore it shouldn’t be followed or promoted.

Specifically, critics believe the carnivore diet uses up too many resources (land, water, etc.) – and that if we want to feed the entire world and support the human population explosion – we need to minimize animal agriculture and simultaneously increase non-animal agriculture (i.e. plant farming).

Counterpoint: Just because a diet is unfeasible for the entire world to follow doesn’t mean that it’s unjustified or shouldn’t be used by a subset of individuals as a tool to improve health.

Some people own large swaths of land and do their own farming. Does this mean that they should be required to share the farmland with others? No.

Some people earn more money than others – does this mean that everyone should receive equal pay? No.

Having a Lamborghini isn’t feasible for everyone either. Should you feel bad if you buy a luxury car because not everyone can have one? No.

Moreover, one could actually argue that increasing meat demands puts greater pressure on society to innovate within the meat industry such as by accelerating the production of – and decreasing costs associated with – cultured meat.

In fact, with ongoing innovation, cultured meat may eventually become very feasible for much of the world to consume.

Others might actually like the idea that allocating land for animal agriculture (to fuel persons on carnivore diets) interferes with non-animal agriculture.

Why? Because this might decrease food availability worldwide – which might subtly reduce the annual rate of worldwide population growth. (Not everyone wants the population to explode at a rapid rate).

Furthermore, despite the fact that the carnivore diet is unfeasible for much of the world, it’s still feasible for many – particularly persons in developed countries like the United States.

Additionally, even if the carnivore diet were feasible for the entire world, most people would NOT follow it – because carbohydrates, fruits, and vegetables are often enjoyable to consume and perceived as healthy/nutritious.

Unnatural. Critics suggest that the carnivore diet is unhealthy because it’s “unnatural.”

Specifically, it is assumed that, because most humans throughout the world consume varied, omnivorous diets (i.e. what’s natural for humans) – any extreme variation (e.g. carnivore, vegan, keto) should be deemed unnatural and therefore unhealthy.

Counterpoint: First off, some carnivore dieters might debate the suggestion that a carnivore diet is unnatural due to the fact that various tribes throughout human history consumed all-meat diets.

Although humans as a whole were historically omnivorous, there are examples of tribes who consumed all-meat diets without substantial adverse health effects (e.g. Greenland Eskimos).

Furthermore, some anthropologists posit that there may have been long periods in which various groups of early humans consumed mostly animal products for energy.

Since: (1) subsets of early humans may have consumed all-meat diets, and (2) most humans consider meat eating natural – one could argue that eating all-meat or mostly meat – is not unnatural.

Secondly, let’s play devil’s advocate and assume that eating an all-meat diet is unnatural such that it’s not what human biology was designed to handle.

Just because our body may not have designed to handle a carnivore diet – does not mean that a carnivore diet cannot provide adequate energy and nutrition – while preserving human health.

In other words, we must consider the possibility that although a carnivore diet may be unnatural for humans – it might also be completely healthy (and possibly healthier) than many other diets.

Thirdly, the perception of what’s natural for humans to eat has dramatically shifted over time.

These days many people think it’s natural to consume breads, bagels, pasta, cereal grains, beans, dairy, cheeseburgers, and pizzas – however, throughout human history, these foods wouldn’t have existed (especially in the formats currently sold at modern-day supermarkets).

In summary, those who argue that the carnivore diet is unhealthy because it is unnatural are completely ignoring that: (1) there’s no universal consensus of a perfect “natural diet” for humans; (2) unnatural is not automatically unhealthy (in some cases “unnatural” dietary choices might be healthier than natural); AND (3) dietary requirements can vary between humans based on genotype.

Counterpoint: It’s not a stretch to assume that the carnivore diet can exacerbate the symptoms of preexisting medical conditions and/or trigger various medical problems in susceptible individuals.

However, most smart people on the carnivore diet will discontinue the carnivore diet immediately if it exacerbates preexisting medical conditions and/or triggers a medical condition.

It makes logical sense to assume that most will NOT try to “tough it out” and continue a diet that’s making them feel worse.

If carnivore is worsening your general health or medical status – you can simply stop eating carnivore; nobody is forcing you to continue.

Zero scientific support. By following a diet without strong scientific support, critics suggest that carnivore dieters may damage their health, shorten their healthspan, and/or increase risk of early mortality (relative to other diets).

Only then could we begin to determine whether certain diets fair better than others for maximizing healthspan and lifespan.

Since we cannot conduct an extremely long-term RCT while simultaneously controlling for all confounding variables (many of which substantially affect health) – some have questioned whether epidemiology is even helpful for establishing general nutritional guidelines.

Certain researchers have stated that:

“The field of nutritional epidemiology has generated confusion and numerous implausible findings and is in need of radical reform.” (R)

Moreover, since one study of adult Greenland Eskimos showed that an all-meat diet was associated with no significant adverse health effects – it could be argued that there’s actually preliminary scientific support in favor of a carnivore diet for health.

If we consider that the carnivore diet: (1) removes many compounds to which many people are allergic/sensitive; (2) eliminates sugar; (3) tends to promote weight loss (usually fat loss); and (4) minimizes risk of overnutrition – one might argue that this could enhance healthspan and/or lifespan.

Additionally, there’s a growing number of people running self-experiments (i.e. N=1) on carnivore and reporting favorable results (such as objective improvements in biomarkers and subjective improvements in mood and cognition).

Though current high-quality epidemiologic data shouldn’t be dismissed altogether (as it may provide some helpful insights) – we cannot know the impact of the carnivore diet on human health until we study the carnivore diet specifically.

In other words, although the consumption of animal products (e.g. red meat) is commonly deemed unhealthy in general nutritional epidemiology – this is not in the specific context of a carnivore diet (i.e. zero carb, zero fiber, zero sugar, zero plants/fruits, etc.).

For this reason, it’s impossible to actually know the general impact of a carnivore diet on health until more studies are conducted.

A combination of short-term randomized controlled trials and ongoing epidemiologic studies should help provide more insight regarding the health effects of a carnivore diet.

Note: If you can think of any other common criticisms of the carnivore diet to add – let me know in the comments.

How can we determine whether carnivore diet (or any diet) is “healthy”?

The most effective way to determine the actual health effects of any diet (including carnivore) is to conduct twin control experiments, knowing SNP heritabilities of diet/exercise response, using within-subject designs for power with small N and modeling heterogeneity.

Because many people report all sorts of health benefits with every single diet, including: vegan, vegetarian, carnivore, keto, paleo, omnivore, etc. – it’s impossible to know whether one diet is superior to another (on average).

Furthermore, with the present abundance of nutritional epidemiological studies, dieters of all types (vegan, paleo, carnivore, keto, etc.) can cherry-pick studies to portray their diet as superior (relative to other diets) for overall health and/or criticize the authors, methods, analyses, funding, etc. of studies that contradict their views.

I’m of the mindset that although certain diets might be healthier than others for a majority of humans – an optimal diet will vary among persons in accordance with gene expression.

Although metabolic ward experiments are generally short-term and wouldn’t reveal long-term health effects of the carnivore diet, they would effectively showcase physiologic and health effects of a carnivore diet (relative to a control diet).

It can be argued that data from nutritional epidemiology is completely useless, however, it’s possible that data from a large-scale epidemiological study of long-term carnivore dieters might help elucidate certain long-term physiologic and health effects of carnivore diets.

If we assess large-scale metabolic ward experiments and long-term epidemiologic studies of the carnivore diet – patterns within the data may reveal legitimate effects of the carnivore diet on health.

Notable Proponents of the Carnivore diet

Amber O’Hearn (Data scientist)

Bart Kay (Former science lecturer)

Frank Tufano (YouTuber)

Georgia Ede (MD)

Jordan Peterson (Psychologist)

Ken Berry (MD)

Kevin Stock (DDS)

Mark Bell (Strength athlete)

Mikhaila Peterson

Paul Saladino (MD)

Shawn Baker (MD)

Tristan Haggard (YouTuber)

Notable Critics of the Carnivore diet

Chris Kresser (Researcher)

Garth Davis (MD)

Joel Fuhrman (MD)

Joel Kahn (MD)

Joe Rogan (Podcaster)

Layne Norton (PhD)

Mark Sisson (Researcher)

Michael Greger (MD)

Rhonda Patrick (PhD)

Note: If I’m missing anyone notable from the above lists (proponents and critics) – let me know so that I can add them.

Final thoughts on the carnivore diet

Though I do not follow the carnivore diet, I think that a well-planned/executed (i.e. nutritionally complete) carnivore diet has potential to be healthy for a subset people for a short-term, moderate-term, and long-term.

In persons with autoimmune disorders, it’s possible that benefits of a carnivore diet are attributable to the induction of mild nutrient deficiencies – as nutrient deficiencies have been shown to suppress immune function.

For this reason, it is likely that calorie reduction and/or fat loss are the critical underlying drivers of health improvements reported among carnivore dieters.

If a nutritionally-complete carnivore diet is objectively (based on biomarkers) and subjectively (based on introspective perception) improving your health – then by all means, continue.

However, if a carnivore diet is causing problems (e.g. bloodwork abnormalities, feeling sluggish, psychological distress, etc.) – then don’t be afraid to discontinue it and try something else.

Popular opinions on the carnivore diet

With many diets, most people will have polarizing opinions (as a result of “black-and-white” thinking) such as: “it’s the healthiest of all” OR “it’s the least healthy.”

The truth is that, whether a diet is healthy will generally be contingent upon the specific person following it – and his/her results.

It’s the healthiest diet for humans.

It’s the least healthy diet for humans.

It’s unclear as to whether it’s healthy or unhealthy long-term. Degree of healthiness or unhealthiness may be contingent upon the specific person following it.

If the carnivore diet causes you to lose body fat, cures your depression, alleviates joint pain, and increases energy – then it may be a great fit for you.

If the carnivore diet causes you to gain body fat, induces depression, exacerbates an autoimmune condition, and/or causes fatigue – then it may be a poor fit for you.

However, just because you have a positive or negative experience with the carnivore diet does not mean that everyone else who has a different experience was “doing the diet wrong,” “lying,” “experiencing a placebo/nocebo effect,” etc.

Similarly, there are probably people who’ve tried the carnivore diet and found it to be relatively neutral in its effect on health (such that its impact wasn’t overwhelmingly positive or negative).

Generally, any diet that: (1) objectively and subjectively improves your health AND (2) that you can adhere to for a long-term – is probably a great choice.

(Also keep in mind that some people can respond well to many different diets – as long as nutritional needs are met, calories aren’t overconsumed, and body composition remains healthy).

Does this mean that a carnivore diet would ruin my health? Not necessarily – in fact, it’s possible that a carnivore diet could improve my health.

Perhaps I will try a short-term experiment with carnivore in the future like the early diet hacker from 1886 (Ben Rhydding) who reported great results (weight loss, mental clarity, etc.) in the British Medical Journal (BMJ).

How I’d do a carnivore diet

Blood pressure & blood sugar. At regular intervals I’d test my blood pressure and blood sugar on the carnivore diet. Assuming I’m losing weight and/or body fat, blood pressure should decrease. Fasting blood sugar can be included with labs but I may monitor it more frequently.

Blood work. At regular intervals I’d get some fasted blood work done to ensure that the carnivore diet isn’t having an adverse impact on my physiology. I would test at the same time of day (each time) and would not test after strenuous exercise.

Ammonia (serum)

Apo B

Blood glucose

Cholesterol (LDL-P, sdLDL-c, Lp(a))

C-reactive protein

Glutathione

Homocysteine

Kidney function panel

Liver function panel

Mineral panel (comprehensive)

Plasma glycine

Sex hormone panel

Thyroid panel

Triglycerides

Urine organic acid

Vitamin panel (comprehensive)

Bowel movements. While on the carnivore diet, I’d make note of my bowel movements and whether I experienced any gastric abnormalities throughout the day. Bowel movement irregularities commonly occur when initially transitioning to carnivore – but should normalize once fully adapted.

Consider dairy. At first I might try the carnivore diet with zero dairy for the simple fact that many people seem to tolerate it better with no dairy. However, because I don’t have allergies or sensitivities to most dairy products, it may be wise to include dairy in the carnivore diet. Why? Because dairy products can provide nutrients that won’t otherwise be attained on the carnivore diet – which should decrease risk of nutrient deficiencies.

Cooking duration & temperature. I’d do my best to avoid overcooking meat on the carnivore diet. Why? Because high cook temperatures and/or excessive cook duration can increase the formation of carcinogenic compounds (e.g. heterocyclic amines, polycyclic aromatic hydrocarbons, etc.). Though the carcinogenic compounds may not be harmful in small doses, if consumed regularly over a long-term, they might do damage. The key is to minimize carcinogenic potential.

Discontinue if adverse effects. If any serious adverse effects surfaced while following a carnivore diet, I’d immediately stop the diet. Persisting with the carnivore diet in the aftermath of serious bloodwork abnormalities would be downright foolish.

Exercise. To minimize the potentially deleterious effects of excess animal protein intake, I’d exercise regularly. I think a combination of resistance training and cardio is probably best, but any type of exercise (including low-intensity steady state like walking) is fine.

Food shopping. In effort to save money and minimize my ecological footprint, I’d search for local livestock farmers and determine prices. I’d go with the farmer(s) who provide the best deals – and would buy meat in bulk to save money (freezing the majority).

Grass-fed, wild caught. On the carnivore diet, I’d attempt to consume most of my meat from pasture-raised, grass-fed cows and fish from wild caught sources. This ensures that meats and fish will be higher in omega-3 fatty acids and nutrients; lower in biotoxins (e.g. pesticides, pollutants, artificial hormones, antibiotics, etc.); and unprocessed.

Intermittent fasting. The health benefits of intermittent fasting are debatable and often don’t hold up when considering confounds (e.g. magnitude of fat loss). Nevertheless, I might try intermittent fasting on carnivore due to the fact that the healthy Greenland Eskimo tribe on an all-meat diet practiced intermittent fasting (i.e. eating to maximum capacity followed by long periods of no food). Timing of intermittent fasting likely matters – so I’d aim for eating an early dinner (and fast throughout the night – rather than skipping breakfast).

Medical checkups. At regular intervals I’d see a medical doctor to determine whether he/she notices any deterioration of my health while on the carnivore diet. Though medical checkups may be unnecessary, medical doctors may discover things that I’m unaware of and/or never checked.

Muscle meat only (?). If I initially had success with a nose-to-tail style carnivore diet for 90 to 180 days, I might then experiment and switch to the Shawn Baker method of “muscle meat only” with zero supplementation for a short-term to assess the impact. Why? Because I believe there could be a beneficial (perhaps transient) hormetic effect associated with consumption of only muscle meat.

Nose-to-tail. Though Shawn Baker may be getting good results by eating nothing but muscle meat, I’d personally rather follow Paul Saladino’s advice and consume a nose-to-tail style carnivore diet (which includes organ meats) to minimize risk of nutrient deficiencies. Why? Because a nutrient deficiency could have serious, potentially life-altering consequences.

Plan meals in advance. To ensure that my carnivore diet is nutritionally-complete, I’d take time to plan out my meals using online nutrition trackers. My goal would be to plan meals that provide (1) sufficient calories and (2) nutrient density.

Sleep & stress. While on the carnivore diet I’d try to ensure that I’m getting adequate sleep each night and properly managing stress. Additionally, I’d track my sleep (using an app) and take note of my stress level (e.g. 1 to 10) in a journal.

Supplements. Though many people can do the carnivore diet without supplementation (especially for a short-term due to preexisting vitamin reserves), I personally won’t rely on hypotheses of carnivore dieters suggesting that vitamin needs go down and/or absorption improves in absence of carbs and fiber. The consequences of vitamin deficiencies are too serious to trust hypotheticals.

Try for 90 days (minimum). It takes time for physiology to adapt to a strict carnivore diet after initiation. Many estimate that full adaptation requires 90 to 180 days (3 to 6 months). For this reason, new carnivore dieters may not know the full capacity of the carnivore diet’s health impact until they’ve stuck with it for at least several months.

Zero raw meat. It’s become popular online to see online “influencers” endorse the consumption of raw meat. Though raw meat may be tolerable (or enjoyable for some), it might also contain pathogenic bacteria that could cause a life-threatening reaction. Moreover, we get fewer nutrients from raw meat than cooked meat. In brief, there’s no logical reason to eat raw meat on carnivore. (R)

Have you tried a carnivore diet?

Below are some questions that you may want to address in your comment.

How long have you been on the carnivore diet?

If a long-term carnivore, how long did it take to adapt?

Did you experience any side effects during the adaptation phase?

Did you make any tweaks to ease your transition to carnivore?

Do you have any preexisting medical conditions?

Are you taking any medications?

What is your height, weight, age, and sex?

Do you take any supplements on the carnivore diet?

Which supplements do you take?

Why do you take these supplements?

What are the dosages?

Have you lost weight on the carnivore diet?

How much weight did you lose?

Was it mostly fat, muscle, or both?

How did the carnivore diet affect your daily functioning?

Athletic/exercise performance

Cognitive performance

Energy level

Mood

Sex drive

Sleep (quality/quantity)

Stress level

Did you get bloodwork done on the carnivore diet?

What specific tests did you have done?

What were the results? (Positive and negative)

If you benefitted from the carnivore diet, why do you think it was so beneficial?

Weight loss and/or fat loss?

Elimination of certain compounds?

Correction of nutrient deficiencies?

What’s a typical day of eating on the carnivore diet like for you?

Did you track calories and macros before/during carnivore?

How did calories compare?

How did macronutrients compare?

What would you rate your satiety on the carnivore diet after each meal? (On a scale from 1 to 10 – assuming “1” is minimal satiety and “10” is maximal satiety).

Do you have any food cravings on the carnivore diet?

What percentage of calories do you consume from fat and protein?

Do you aim for a nose-to-tail style carnivore diet – or do you only eat muscle meat?

What is your favorite meal on the carnivore diet?

Do you include dairy in your carnivore diet?

How are your bowel movements on the carnivore diet?

Do you plan on following the carnivore diet for life – or using it transiently as a tool for weight loss?

Carnivore diet resources…

Carnivore diet general information & discussions…

What I’ve Learned: Carnivore Diet: WhatIveLearned (WIL) is a YouTuber who creates concise, easy-to-understand, well-researched videos that explain “what he’s learned.” This is a fantastic video he created about the carnivore diet.

Dr. Shawn Baker on Joe Rogan Experience: Joe Rogan hosts Dr. Shawn Baker on the “Joe Rogan Experience” for a full-length discussion about how he got into the carnivore diet, why he’s continued the diet , and why he thinks the carnivore diet is healthy. Joe questions Shawn about his exercise habits, bloodwork, ethics of the carnivore diet, whether he supplements (he doesn’t) – and more.

The Carnivorous Human: L. Amber O’Hearn (data scientist) has followed a carnivore diet long before it became popular in the mainstream. Back in 2017, Amber gave a speech about her diet history (vegan, then low-carb, then carnivore) – and the health benefits she’s noticed on a carnivore diet.

The Plural of Anecdote is Data: Lessons from N=Many: Shawn Baker (MD) gives a speech at CarniovoryCon 2019 about why he thinks the plural of anecdote is data – particularly regarding favorable anecdotes on a carnivore diet. (This runs contrary to the commonly-used expression: “the plural of anecdote is not data.”)

The Brain Needs Meat: Health Benefits of Carnivore: Georgia Ede (MD) is a psychiatrist who has found the carnivore diet helpful for reversing her fibromyalgia, migraines, chronic fatigue syndrome, and IBS. She also emphasizes the importance of consuming animal products for brain health.

Plant Defense Chemicals, The Dark Side of Plant Foods: George Diggs (PhD in biology) is a professor and director of Public Health at Austin College. He specializes in researching things like evolution and human health – and evolutionary mismatches between how humans evolved and how humans currently live.

Danny Roddy 2-Year Carnivore Diet Review: A YouTuber named Danny Roddy followed the carnivore diet from 2008 to 2010 (long before it became the latest fad). In this video, Danny shares his experience with the carnivore diet, addresses why he thinks some people respond well to the carnivore diet (especially initially), and hypothesizes why the carnivore diet may be problematic (particularly over a long-term).

Georgia Ede on Mark Bell’s Power Project: Georgia Ede (MD), a psychiatrist (and nutritional consultant), joints Mark Bell’s “Power Project” to discuss the benefits of following a carnivore diet. She was able to reverse many of her own health conditions like CFS, IBS, fibromyalgia, and migraines.

Mikhaila Peterson on the Carnivore Diet: Jordan Peterson’s daughter, Mikhaila Peterson, joined the “Joe Rogan Experience” to discuss her favorable experience with the carnivore diet. Mikhaila claims that she went on a restrictive diet in attempt to manage a variety of serious health issues (juvenile arthritis, brain fog, major depression, etc.) – and that a “meat-only” carnivore diet is what makes her feel best.

Frank Tufano: 6 Years on the Carnivore Diet: As of December 2018, a YouTuber named Frank Tufano made a video in which he claimed to followed the carnivore diet for over 6 years. This video explains why Frank initially pursued a carnivore diet and subjective health benefits that he’s experienced on the diet.

What if you at only meat? (ASAPSCIENCE): The YouTube channel ASAPSCIENCE created a short video in which they address the question “what if you ate only meat?” The YouTubers expalin what would likely happen within your body and to your overall health if you followed an “all-meat” (i.e. carnivore) diet.

The Truth About the Carnivore Diet: Ben Greenfield (athlete, biohacker, etc.) hosts Paul Saladino (MD) for a full-length discussion about the health effects of a carnivore diet.

Elliott Hulse & Paul Saladino (MD): Elliott Hulse hosts a conversation on his YouTube channel with Paul Saladino (MD) about the carnivore diet – and goes as far as to infer that “veggies are trash” in his video thumbnail. Elliott describes his experience with low carb diets & the carnivore diet (including the impact of removing carbs on his exercise performance).

Carnivore Diet Myths Debunked: Tristan (Primal Edge Health) hosts a conversation with Paul Saladino (MD) in which they debunk myths and misconceptions about the carnivore diet.

Shawn Baker (MD): Shawn Baker is [arguably] the godfather of the modern carnivore diet movement. He transparently discusses his own health on the carnivore diet and frequently refutes criticisms of the carnivore diet.

Paul Saladino (MD): In my opinion, Paul Saladino provides the most comprehensive information about the carnivore diet on the internet. If you’re interested in trying the carnivore diet – watch his videos.

L. Amber O’Hearn: L. Amber O’Hearn (data scientist and nutrition researcher) has a YouTube channel in which she compiles videos related to the carnivore diet. She isn’t regularly active on her personal YouTube account – but she has some fantastic carnivore diet-related videos.

Sv3rige: This is a controversial YouTuber who formerly followed a vegan diet – and eventually transitioned to a raw carnivore diet. He regularly consumes raw animals and animal products – including aged “high” (i.e. rotten) meats because he perceives these things as healthiest and natural for humans. He is also a notable “anti-vegan” in which he regularly antagonizes vegans (at vegan events) and suggests that veganism provides zero nutrients for human health.

Carnivore diet criticisms…

Joel Fuhrman on Mark Bell’s Power Project: Joel Fuhrman (MD) joins Mark Bell’s “Power Project” to discuss the effects of diet on health. Joel is a strong critic of the carnivore diet and meat consumption. He argues that meat is carcinogenic – and that fruits and vegetables enhance health via nutrient and antioxidant content.

Dr. Rhonda Patrick on the Carnivore Diet: Rhonda Patrick (PhD in biomedical science & nutrition/cancer researcher) joins the “Joe Rogan Experience” to discuss many topics – one of which is the carnivore diet (~13:22 into the podcast). Rhonda voices her concerns about the carnivore diet and has allegedly written ~13 pages of notes on the diet (something I would like to read). (I agree with Rhonda here – that many benefits from the carnivore diet may be attributable to caloric restriction [even if unintended via dietary monotony] and possibly intermittent fasting.

Shawn Baker’s rebuttal: Shawn Baker watched Rhonda Patrick on the Joe Rogan Experience and responded to many of her claims.

The Carnivore Diet is BS: YouTuber “Hench Herbivore” (a vegan bodybuilder) created a video explaining why he thinks the carnivore diet is a horrible choice for most people.

Ben Greenfield on Joe Rogan: Ben Greenfield (athlete, biohacker, health coach, etc.) joins the “Joe Rogan Experience” and shares his opinion on the carnivore diet – and why people like Jordan Peterson are benefitting from it.

Dom D’Agostino & Layne Norton on Joe Rogan: Layne Norton (PhD in nutrition) and Dom D’Agostino (PhD in neuroscience & physiology / research scientist) discuss the effects of various diet types on health. Layne is an advocate for flexible-dieting and Dom is an advocate for ketogenic dieting. (I think they briefly discuss carnivore).

Layne Norton (PhD) vs. Shawn Baker (MD): Layne Norton (PhD in nutrition) debates Shawn Baker (MD) on Mark Bell’s “Power Project” podcast. I’d say this is more of a cordial discussion than a debate. Layne may be better-versed in nutritional research than Shawn – and Shawn may be better-versed in medical research (e.g. disease rates) than Layne… each make some fantastic points. Shawn highlights the major problems with relying upon “associational” (i.e. epidemiological) studies to influence health recommendations. Layne and Shawn agree on many things here… Overall, a highly-productive discussion.

Vegan Gains vs. Sv3rige: This is a 2 vs. 2 debate between Sv3rige and Milk Jar (carnivore dieters) and Vegan Gains and Ask Yourself (vegan dieters). Sv3ridge argues that a carnivore diet is natural for humans and therefore the healthiest – whereas the vegans argue that a vegan diet is healthiest for humans based on epidemiology.

Garth Davis vs. Bart Kay: Garth Davis (MD) and Bart Kay discuss general science, nutritional science, and how they interpret the totality of nutritional science. For those unfamiliar, Garth Davis is a well-known vegan medical doctor who promotes a whole-foods plant based diet – and Bart Kay is a carnivore diet advocate.

Carnivore diet websites

JustMeat.co: This is a website created by Michael Goldstein that serves as a repository for all of the best carnivore diet-related content on the internet. (Check it out).

Zero Carb (Reddit): The Zero Carb (ZC) community on Reddit is a great resource for learning more about the carnivore diet – and has an extremely active community. If you have any questions about the carnivore diet or want to join a carnivore community – this one is fantastic.

Empiri.ca: This is a website created by L. Amber O’Hearn (data scientist) that documents her: (1) experiences with the carnivore diet, (2) carnivore diet research, and (3) interpretations of nutritional research.

Shawn Baker: This is the official website of Shawn Baker (MD) – the most prominent carnivore diet advocate.

Diagnosis Diet: Diagnosis Diet is a website created by Dr. Georgia Ede, a psychiatrist who follows a carnivore diet herself – and who underscores the importance of consuming animal products.

Kevin Stock: Kevin Stock is a dentist (DDS) who follows the carnivore diet – and has written some great content about the carnivore diet.

Meat Heals: This is a website established to compile anecdotes from individuals who experienced major health improvements and/or remission of medical conditions/symptoms as a result of switching to the carnivore diet.

Zero Carb Health: This website was established in 2015 and contains articles about zero carb/carnivore diets.

Note: The author of this site is not engaged in rendering professional advice or services to the individual reader. The ideas, procedures, and suggestions contained within this work are not intended as a substitute for professional advice. I shall not be liable or responsible for any loss or damage allegedly arising from any information or suggestions within this website.